Yemen: Civil War and Regional Intervention

Yemen: Civil War and Regional Intervention

Yemen: Civil War and Regional Intervention
November 23, 2021
For over a decade, the Republic of Yemen has been torn apart by multiple armed conflicts to
which several internal militant groups and foreign nations are parties. Collectively, these
Jeremy M. Sharp
conflicts have eroded central governance in Yemen and hav e fragmented the nation into various
Specialist in Middle
local centers of power. The gradual dissolution of Yemen’s territorial integrity has alarmed the
Eastern Affairs
United States and others in the international community. Policymaker concerns include fears that

state failure may empower Yemen-based transnational terrorist groups; destabilize vital
international shipping lanes near the Bab al Mandab strait (also spelled Bab al Mandeb, Bab el

Mendeb); and provide opportunities for Iran to threaten Saudi Arabia’s borders.
Beyond geo-strategic concerns, the collapse of Yemeni institutions during wartime has exacerbated poor living conditions in
what has long been the most impoverished Arab country, leading to what is now considered one of the world’s worst
humanitarian crisis. This report provides information on these ongoing and overlapping crises.
In 2014, the northern Yemeni-based Ansar Allah/Houthi movement (referred to in this report as “the Houthis”) took over the
capital, Sana’a (also commonly spelled Sanaa), and in early 2015, advanced southward from the capital to Aden on the
Arabian Sea. In March 2015, after Yemeni President Abdu Rabbu Mansour Hadi, who had fled to Saudi Arabia, appealed for
international intervention, Saudi Arabia assembled a coalition of several of its Arab partners (referred to in this report as “the
Saudi-led coalition”) and launched a military offensive aimed at restoring Hadi’s rule and dislodging Houthi fighters from the
capital and other major cities.
Since then, the conflict in Yemen has killed tens of thousands, caused significant humanitarian suffering, and has
significantly damaged the country’s infrastructure. One U.S.- and European-funded organization, the Armed Conflict
Location & Event Data Project (ACLED), estimates as of October 2021 that more than 145,000 Yemenis have been killed
since 2015.
Although media coverage of the Saudi-led intervention has characterized the war as a binary conflict (the Saudi-led coalition
versus the Houthis), there actually have been a multitude of combatants whose alliances and loyalties have been somewhat
fluid. In summer 2019 in southern Yemen, long-simmering tensions between the internationally recognized Republic of
Yemen government (ROYG) and the separatist Southern Transitional Council (STC) boiled over, leading to open warfare
between the local allies of Saudi Arabia and the United Arab Emirates. Since then, periodic clashes have continued, though
both sides finally implemented a power sharing agreement at the end of 2020 and formed a tenuous coalition government.
Since early 2020, Houthi forces have continued to launch attacks against the ROYG in Marib governorate. The Marib
governorate is the last northern stronghold of the ROYG. During summer and fall 2021, momentum shifted in favor of the
Houthis, as their fighters have gradually attempted to encircle Marib city, the governorate’s eponymous capital. Between
September and October 2021, the Houthis captured five districts in the governorates of Marib and Shabwa, effectively cutting
off the southern road linking Marib City to Shabwa—a key route for the resupply of ROYG forces. The Houthis have made
significant territorial gains in Marib and may be on the cusp of forcing ROYG forces to surrender or negotiate a cease-fire.
Many foreign observers have denounced human rights violations that they charge have been committed by all parties to the
conflict. In the United States and some European countries, there has been vociferous opposition to Saudi-led coalition air
strikes that hit civilian targets, leading Congress to debate and enact some legislation to limit U.S. support for the coalition.
Some in Congress opposed to such efforts have highlighted Iran’s support for the Houthis as a major factor in Yemen’s
destabilization.
For several years, Yemen has been considered one of the worst humanitarian crises in the world, and public health experts
warn that the Coronavirus Disease 2019 (COVID-19) pandemic is having significant negative effects on Yemen’s vulnerable
population. To date, most humanitarian agencies believe that the extent of the outbreak in Yemen has been underreported.
For additional information on Yemen, including a summary of legislation under consideration in the 117th Congress, please
see CRS Report R45046, Congress and the War in Yemen: Oversight and Legislation 2015-2021, by Jeremy M.
Sharp, Christopher M. Blanchard, and Sarah R. Collins.
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Contents
Overview ....................................................................................................................... 1
Conflict Update .............................................................................................................. 2
The Houthi-ROYG War in the North: The Battle for Marib .............................................. 2
Other Houthi Military Gains........................................................................................ 3
The Port of Hudaydah ................................................................................................ 5
The Maritime Blockade and Fuel Shipments into Hudaydah ....................................... 5
Failing Oil Tanker ................................................................................................ 7
The Houthi-Saudi Arabia Conflict ................................................................................ 8
Peace Efforts Stal ........................................................................................................... 9
Iranian Support to the Houthis......................................................................................... 10
Southern Yemen: Tentative Unity between the ROYG and STC............................................ 11
Biden Administration Policy...................................................................................... 12
Yemen’s Humanitarian Crisis .................................................................................... 14
Food Insecurity & Humanitarian Access ................................................................ 15
The COVID-19 Pandemic in Yemen...................................................................... 16
International Pledges for Yemen ........................................................................... 17
Conflict Analysis ..................................................................................................... 17

Figures
Figure 1.Marib Governorate.............................................................................................. 3
Figure 2. Lines of Control in Yemen................................................................................... 4
Figure 3. U.N. Monitors in Hudaydah ................................................................................ 5
Figure 4. Saudi-led Coalition Air Strikes per Month ............................................................. 9
Figure 5. World Food Programme: Emergency Dashboard Yemen ........................................ 16

Contacts
Author Information ....................................................................................................... 19

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Yemen: Civil War and Regional Intervention

Overview
For over a decade, the Republic of Yemen has been torn apart by multiple armed conflicts to
which several internal militant groups and foreign nations are parties.1 Collectively, these
conflicts have eroded central governance in Yemen and have fragmented the nation into various
local centers of power. The gradual dissolution of Yemen’s territorial integrity has alarmed the
United States and others in the international community. Policymaker concerns include fears that
state failure may empower Yemen-based transnational terrorist groups; destabilize vital
international shipping lanes near the Bab al Mandab strait2 (also spel ed Bab al Mandeb, Bab el
Mendeb); and provide opportunities for Iran to threaten Saudi Arabia’s borders. Beyond geo-
strategic concerns, the collapse of Yemeni institutions during wartime has exacerbated poor living
conditions in what has long been the most impoverished Arab country, leading to what is now
considered one of the world’s worst humanitarian crises.
Since March 2015, Saudi Arabia and members of a coalition it established have been engaged in
military operations in Yemen against the Houthi movement, or Ansar Allah, which the U.S.
government believes receives some material support from Iran. As of November 2021, the
epicenter of fighting was around the northern governorate and city of Marib, one of the last areas
under the control of the international y-recognized Republic of Yemen Government (ROYG) led
by Yemeni President Abdu Rabbu Mansour Hadi.
As of November 2021, Yemen remains beset by multiple armed and political conflicts which, in
their totality, have crippled central governance, devastated the national economy, and exacerbated
a long-standing humanitarian crisis. The Armed Conflict Location & Event Data Project
(ACLED) estimates that from the start of regional intervention in Yemen in March 2015 until
October 2021, over 145,000 Yemenis had been kil ed in various acts of violence.3

1 Formerly the Republic of North Yemen and the People’s Democratic Republic of [South] Yemen, Yemen has been a
unified republic since 1990 in which, according to Article 4 of its 2001 constitution (as amended), “T he people of
Yemen are the possessor and the source of power, which they exercise directly through public referendums and
elections, or indirectly through the legislative, executive and judicial authorities, as well as through elected local
councils.” In reality, from 1990 to 2012, the late President Ali Abdullah Saleh ruled the unified Yemen continuously,
centralizing power and control under his auspices through partnerships with foreign powers and local power brokers.
After popular uprisings swept across the Arab world in 2011, including in Yemen, the Gulf Cooperation Council
(GCC) helped broker a transition plan for Yemen, which was endorsed by the United Nations (see, U.N. Security
Council Resolution 2014) and superseded the authority of Yemen’s constitution. As part of Yemen’s transition from
the longtime rule of President Saleh to interim President Hadi (Saleh’s long-time Vice President), all of Yemen’s
various political factions (565 individual delegates) held what was called the National Dialogue Conference (NDC)
from 2013-2014. T hat conference was intended to settle all of Yemen’s outstanding political issues, including
producing recommendations which were to be used by a Constitutional Drafting Committee to create a new
constitution, which would then be voted on in a national referendum. Howev er, in January 2014 the NDC ended
without agreement and shortly thereafter, the Houthis launched a military offensive to seize large swaths of northern
Yemen, culminating in their capture of the capital Sanaa in September 2014 .
2 After the Straits of Hormuz and Malacca, the Bab al Mandab is one of the world’s busiest chokepoints in terms of
volume of crude oil and petroleum liquids transported through each day. According to the Energy Information
Administration, “ T otal petroleum flows through the Bab el-Mandeb Strait accounted for about 9% of total seaborne-
traded petroleum (crude oil and refined petroleum products) in 2017.” See, U.S. Energy Information Administration,
“T he Bab el-Mandeb Strait is a Strategic Route for Oil and Natural Gas Shipments, August 27, 2019.
3 T he Armed Conflict Location & Event Data Project (ACLED), Dashboard, available online at
https://acleddata.com/dashboard/#/dashboard.
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Conflict Update
The Houthi-ROYG War in the North: The Battle for Marib
Since early 2020, Houthi forces have continued to launch attacks against the forces of the
Republic of Yemen Government (ROYG) in Marib governorate. The Marib governorate is the last
northern stronghold of the ROYG. Marib is the center of Yemen’s modest hydrocarbon sector
and, while the country imports over 90% of its oil and gas, Marib contains several oil fields
(where Exxon and Total SA have concessions) and an oil refinery that accounts for nearly 8% of
Yemen’s total energy needs.4 Marib also contains a power plant and a liquefied petroleum bottling
plant that produces cooking gas for a significant segment of the population.
At first, the Houthi’s offensive against Marib made only incremental progress.5 During the spring
and early summer of 2021, the Houthis took heavy casualties from Saudi-led coalition air strikes.
The terrain near Marib city itself is relatively flat desert plain, which exposes the Houthi ranks
and make it more chal enging for their fighters, who are accustomed to fighting on mountainous
terrain.6
During summer and fal 2021, momentum shifted in favor of the Houthis, as their fighters have
gradual y attempted to encircle Marib city, the governorate’s eponymous capital. Between
September and October 2021, the Houthis captured five districts in the governorates of Marib
(see Figure 1) and Shabwa (a governorate which also has oil fields and the country’s sole
liquefied natural gas terminal), effectively cutting off the southern road linking Marib City to
Shabwa—a key route for the resupply of ROYG forces.7
In early 2021, Marib was home to an estimated 800,000 internal y displaced persons (IDPs), who
fled conflict in other parts of the country.8 Now, with the conflict having spread throughout the
province, Marib residents are now being displaced. In early October 2021, the International
Organization for Migration announced fighting during September had displaced 10,000 people,
the most in a single month in 2021.9
In an attempt to support ROYG forces and prevent further Houthi encroachment on Marib City,
the Saudi-led coalition has repeatedly conducted air strikes against Houthi ground forces.
Throughout September and October 2021, the Saudi Press Agency has published near daily
reports of the Houthi death toll from coalition air strikes. From October 12 to October 26, the
coalition claims to have kil ed over 1,800 Houthi fighters.10 However, according to Elana
DeLozier, a senior fel ow at the Washington Institute for Near East Policy, “You can’t real y win
a war with air power... And this is where the government real y gets itself into trouble because it

4 International Crisis Group, “Crisis in Marib: Averting a Chain Reaction in Yemen,” February 22, 2021.
5 Samy Magdy, “Grueling Battle for Key Yemeni City; T oll Keeps Rising as Rebels T ry to Complete T heir Hold on the
North But Gain Little,” Associated Press, July 12, 2021.
6 Michael Horton, “Yemen’s Fate Hinges on T he Battle for Marib,” The Jamestown Foundation, Terrorism Monitor,
Volume: 19 Issue: 4, February 26, 2021.
7 “Yemen’s Houthis Advance in Shabwa and Marib,” Reuters, October 17, 2021.
8 Office of the United Nations High Commissioner for Human Rights (UNHCR), “Press briefing notes on Yemen,”
February 19, 2021.
9 Samy Magdy, “UN: 10,000 Displaced as Clashes Escalate Over Key Yemen City,” Associated Press, October 7,
2021.
10 “Saudi Coalition Says Killed 85 rebels Around Yemen’s Marib,” Agence France Presse, October 26, 2021.
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doesn’t have enough oomph to push out the Houthis, so it’s just the Saudi airstrikes [holding
them back].”11 According to one estimate, the Houthis have lost nearly 15,000 fighters since June,
while ROYG-aligned forces fighting in Marib have lost 1,200.12
Figure 1.Marib Governorate

Source: United Nations Office for the Coordination of Humanitarian Affairs
Other Houthi Military Gains
Beyond Marib, the Houthis continue to gain territory on the ground, while using unmanned aerial
vehicles (UAVs) and rockets and missiles to threaten their opponents in other parts of Yemen
beyond their immediate control. Recent notable Houthi campaigns/attacks include:
 In 2021 in the central governorate of Al Bayda, forces aligned with the ROYG
initial y pushed the Houthis back. However, in September 2021, the Houthis
declared full control over the governorate. According to the International Crisis
Group, “Since late September [2021], the Houthis have used al-Bayda as the
launching pad for a multi-front campaign in western Shebwa [Shabwa] and
northern Abyan.... These moves appear to be aimed at cutting off the major roads
linking the three governorates, and the various anti-Houthi forces based inside

11 Siobhán O’Grady and Ali Al Mujahed, “Battle for the Badlands: Yemen’s Seven -Year Civil War Could T urn on
Fierce Fighting in Remote Marib Province,” Washington Post, October 1, 2021.
12 T alek Harris, “Yemen 'Confident' of Holding Key City of Marib, FM Says,” Agence France Presse, November 21,
2021.
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them, as wel as at providing Houthi forces with new routes into southern
Yemen.”13
 In August 2021, a Houthi UAV attack against a military base in the southern
governorate of Lahj kil ed at least 30 soldiers.14 A month later, a combined
Houthi UAV/missile attack struck the port of Mokha, destroying several
warehouses fil ed with humanitarian goods. The attack coincided with the visit of
the ROYG Ministry of Transportation to mark the reopening of Mokha
commercial port, which had been closed for several years.
Figure 2. Lines of Control in Yemen
As of October 2021

Source: Graphic created by CRS using data from Risk Intel igence (2021); Esri (2017 & 2018); NOAA (2018);
USGS (2018); Department of State (2015).

13 International Crisis Group, “After al-Bayda, the Beginning of the Endgame for Northern Yemen,” Briefing 84,
Middle East & North Africa, Oct ober 14, 2021.
14 Olivia Harper, “Ansar Allah Ballistic Missile and UAV Attack Demonstrates Extensive Weapons Arsenal and
Enhanced Operational Capabilities,” Jane's Terrorism & Insurgency Monitor, September 8, 2021.
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The Port of Hudaydah
In December 2018, the United Nations brokered a cease-fire, known as the Stockholm
Agreement,15 centered on the besieged Red Sea port city of Hudaydah (also spel ed Hodeidah, Al
Hudaydah). Nearly three years later, the agreement remains unfulfil ed.
Currently, the Houthis control the port and
city of Hudaydah itself, along with access to
Figure 3. U.N. Monitors in Hudaydah
the city from the north. To the south along the
Red Sea coast, a coalition of forces (dubbed
the “Joint Resistance Forces”) led by Tareq
Saleh, the nephew of the late former Yemeni
President Ali Abdullah Saleh, had remained
ensconced there since 2018, when the Saudi-
led coalition attempted to seize Hudaydah
from the Houthis before the Stockholm
Agreement halted the fighting. Tareq Saleh’s
forces had been based out of the port town of
Mokha and receive support from Saudi
Arabia and the United Arab Emirates. They
are not formal y part of the ROYG and

operate independently from President Hadi.
Source: Twitter, U.N. Mission to support the

Hudaydah Agreement, October 15, 2020.
In November 2021, elements of the Joint
Resistance Forces suddenly withdrew from their positions around Hudaydah City. Houthi forces
then immediately moved in. However, other militias within the Joint Resistance Forces opted to
fight Houthi forces in Hudaydah governorate, as major clashes and air strikes resumed in and
around Hudaydah for the first time since 2018. After the reported redeployment of the Joint
Resistance Forces, Saudi Arabia denied that it was abandoning its support for local Yemeni forces
and withdrawing from Yemen.16 It is possible that Saudi Arabia may be seeking local
reinforcements to counter the Houthis siege of Marib.
The Maritime Blockade and Fuel Shipments into Hudaydah
On April 14, 2015, the U.N. Security Council adopted Resolution (UNSCR) 2216, which
imposed sanctions on individuals undermining the stability of Yemen and authorized an arms
embargo against the Houthis and their al ies. The resolution also demanded that the Houthis
withdraw from al areas seized during the current conflict, relinquish arms seized from military
and security institutions, cease al actions fal ing exclusively within the authority of the legitimate
Government of Yemen, and fully implement previous Council resolutions.
UNSCR 2216 authorizes U.N. member states to prevent the transfer or sale of arms to the Houthis
and al ows “states neighboring Yemen” to inspect cargo suspected of carrying arms to Houthi

15 T he Stockholm Agreement consists of three components: (1) a cease-fire around the port city of Hudaydah, (2) a
15,000-person prisoner swap, and (3) a statement of understanding that all sides would form a committee to discuss the
war-torn city T aiz. T he United Nations agreed to chair a Redeploy ment Coordination Committee (RCC) to monitor the
cease-fire and redeployment. In January 2019, the United Nations Security Council passed UNSCR 2452, which
authorized the creation of the United Nations Mission to support the Hudaydah Agreement (UNMHA), of which the
RCC was a significant component. It has since been reauthorized until July 2022.
16 “Clashes Erupt in Yemen's Hodeidah as Pro-Coalition Forces Cede Ground to Houthis,” Reuters, November 14,
2021.
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fighters. Since the start of hostilities in Yemen, Iran has continued to support Houthi militias with
weapons shipments, fueling the desire of the Saudi-led coalition to thwart Iranian weapons
smuggling by sea (see below).
Between 2015 and 2016, the Saudi-led coalition conducted its own exclusive naval blockade of
Yemen’s ports in order to deter Iranian weapons smuggling. The initial blockade also slowed the
delivery of commercial goods to Yemen. Before the war, Yemen imported nearly 90% of al food.
Near Hudaydah, ships fil ed with food and fuel routinely sat off-shore, as Arab coalition vessels
searched them for il icit arms.17
In order to implement the cargo inspection authority delineated in UNSCR 2216 and expedite the
delivery of commercial goods while maintaining the arms embargo, the international community
created a new inspections regime. In early 2016, the United Nations, at the request of the ROYG,
established the U.N. Verification and Inspection Mechanism (UNVIM).18 UNVIM is a U.N.-led
operation designed to inspect vessels sailing to Yemeni ports not under ROYG control for il icit
weapons. UNVIM can inspect cargo, while also ensuring that commercial items are imported in a
timely manner.
Typical y, UNVIM processes clearance requests from commercial shippers. After reviewing each
request, UNVIM decides to either: (1) not require inspection and grant vessel clearance; or (2)
inspect the vessel in territorial or international waters based on suspicions of the vessel’s
movements, crew, documents, or prohibited cargo. If prohibited items are found during an
inspection, they are to be seized and disposed of by the Government of Djibouti in the presence of
UNVIM Monitors. If a vessel fails to adhere to UNVIM procedures, standard operating procedure
dictates that UNVIM wil contact the Saudi-led coalition’s Evacuation and Humanitarian
Operation Cel (EHOC) at the Saudi Ministry of Defense.
One chal enge to ensuring timely delivery of commercial goods to Yemen is that the ROYG and
Saudi-led coalition employ an additional vessel clearance process subsequent to the UNVIM
clearance. This “secondary” vessel clearance process occurs after UNVIM completes its due
diligence. After UNVIM clears a vessel, it must proceed to what is referred to as the “Coalition
Holding Area” or CHA off the coast of Saudi Arabia, where it must await permission from the
ROYG and the EHOC to dock in Houthi-controlled Yemeni ports.19 Depending on the level of
acrimony between the ROYG and the Houthis, the delay from this secondary clearance process
can range from minimal to a serious impediment to the importation of products into Yemen.

17 “Arab Coalition Navy Inspections Paralyze Yemen Food Shipments,” Reuters, September 10, 2015, and “U.S. T ells
U.N. it Wants to See Boost in Shipping into War-T orn Yemen,” Reuters, September 30, 2015.
18 For background, see United Nations, “In Hindsight: T he Story of the UN Verification and Inspection Mech anism in
Yemen,” UN Security Council Report, September 2016.
19 T he United States has been working with ROYG and Saudi officials for several years to reduce the waiting time for
vessels in the CHA. In a 2018 hearing on Yemen, a USAID official said, “We have been working very carefully—the
State Department, USAID, other donors—with the coalition to reduce the time that the EHOC process—that is the
coalition’s Evacuation Humanitarian Assistance Operations Cell. In the month of April 3 rd [2018], we got that down to
about 3 to 4 days. So it is not 100 days. T here has been a lot of work done getting the communication between that
process and the U.N. verification and inspection mechanism process together. T he U.N. system, UNVIM, gets back
within 48 hours on a determination of whether or not a vessel actually needs to be searched or not, and then it goes
through the EHOC process. We have seen, particularly in the last 6 weeks, significant progress on that, and we are
looking forward to reducing those times even more. What we do need is we need shippers in the region to know how
long it will take and that will, hopefully, get more shipping back into Hudaydah Port, particularly compartmentalized
cargo.” T estimony of USAID Bureau for Democracy, Conflict, and Humanitarian Assistance Deputy Assistant
Administrator Robert Jenkins, Senate Committee on Foreign Relations, U.S. Policy in Yemen, hearing, 115th Cong.,
2nd sess., April 17, 2018, S.Hrg. 115-778 (Washington, DC: GPO, 2020).
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Earlier in 2021, a dispute between the ROYG and the Houthis led ROYG officials to deny
clearance to fuel tankers, some of which lingered off the shores of Hudaydah port for months.
This led to fuel price shortages and rising prices inside Yemen.20 According to a U.S. State
Department spokesperson, the U.S. government opposes arbitrary restrictions of commodities
entering Yemen, but respects “the right of the government to control its access to ports.”21 As of
July 2021, USAID reported:
Fuel shortages continue to contribute to sharp increases in fuel prices across Yemen,
limiting access to essential services. The Republic of Yemen Government (RoYG) and the
Kingdom of Saudi Arabia (KSA)-led Coalition approved four vessels carrying
approximately 89,000 metric tons (MT) of fuel to discharge at Al Hudaydah Port—the
primary entry point for fuel in northern Yemen—during June, according to the United
Nations Verification and Inspection Mechanism for Yemen (UNVIM). UNVIM reports a
38 percent decrease in fuel discharged at Al Hudaydah in June 2021 compared with the
average fuel discharged monthly in 2020; to date in 2021, fuel imports at Al Hudaydah are
down by approximately 82 percent compared with the total amount of fuel imports at the
port in 2020.22
In October 2021, the United Nations Security Council cal ed on the government of Yemen to:
facilitate, regularly and without delay, the entry of fuel ships into Hudaydah port and
emphasized the importance of all parties ensuring the free flow of fuel inside the country
to deliver essential commodities and humanitarian aid, and underscored that fuel that
arrives through Hudaydah port should not be used for personal profit or to fund escalation
of the conflict. They urged the parties to work towards the stability of Hudaydah, including
through cooperation with the United Nations Mission to Support the Hudaydah Agreement
(UNMHA). They called for an end to the encirclement of Al‑Abdiyah.23
Failing Oil Tanker
Moored off of Yemen’s west coast north of Hudaydah, the 44-year-old floating storage and
offloading (FSO) Vessel Safer (owned by the state-run Yemen Oil and Gas Corporation) has been
deteriorating for years. It holds an estimated 1.4 mil ion barrels of crude oil. Routine maintenance
on the tanker stopped after the Saudi-led intervention began in March 2015. If the FSO Safer
were to critical y fail, it would likely cause environmental damage within the Red Sea and would
possibly put supplies of drinking water in danger due to its proximity to desalination plants. It
could also force the port of Hudaydah to close for months, which would obstruct the supply of
humanitarian aid to north Yemen. In order to assess the danger, the United Nations had been
negotiating with the Houthis to permit a technical team access to the tanker. Although the Houthis
had indicated that they would issue entry permits to U.N. inspectors, they have not given their
final authorization. One U.N. spokesperson said that while the U.N. has committed $3.3 mil ion
to begin work on the Safer, the Houthis may be reconsidering al owing them access.24
In October 2021, researchers from Stanford University, Harvard University, and UC Berkeley
published research on the possible impact of an oil spil from the FSO Safer. According to their

20 Nima Elbagir and Angela Dewan, “First Fuel Ship this Year Docks in Hodeidah as Saudi-led Coalition Relaxes
Blockade,” CNN, March 26, 2021.
21 “‘It is not a Blockade’: US says Saudi Arabia isn’t to Blame for Yemen’s Fuel Shortage,” Vox.com, April 14, 2021.
22 USAID, Yemen, Complex Emergency, Fact Sheet #6, July 16, 2021.
23 United Nations, Security Council Press Statement on Yemen, U.N. Document SC/14671, October 20, 2021.
24 Rick Gladstone, “ U.N. Delays Salvage of Yemen Oil T anker Amid Fears of Major Spill,” New York Times, February
2, 2021.
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model, a serious rupture of the FSO Safer would result in a spil that could lead to “nine mil ion
[people] losing access to clean water and seven mil ion losing access to food supplies.”25
The Houthi-Saudi Arabia Conflict
Since a Saudi-led coalition intervened on behalf of the ROYG in 2015, the Houthis and coalition
forces have been engaged in what is referred to informal y as an air and missile war. The Saudis
have conducted numerous air strikes in northern Yemen, while the Houthis have launched
bal istic missiles and unmanned aerial vehicles (UAVs) into Saudi territory. As of 2021, reports of
errant Saudi air strikes that have resulted in civilian casualties continue, though far less frequently
than in earlier periods of the war. The Yemen Data Project, a non-profit independent data
collection project, has tal ied over 23,627 Saudi-led coalition air strikes since March 2015,
resulting in over 18,600 civilian casualties.26
While the Houthis do not possess manned aircraft, they have conducted persistent bal istic missile
and UAV launches against Saudi territory in a campaign they now describe as a response to the
Saudi-led coalition’s ongoing maritime blockade of Yemen’s west coast and closure of Sana’a
airport. In September 2021, Secretary of State Blinken condemned an attack against the Eastern
Province of Saudi Arabia that injured two children and damaged several homes.27  

25Abubakr Al Shamahi, “‘Looming Disaster’: Oil Ship Leak T hreatens Millions of Yemenis,” Al Jazeera English,
October 11, 2021. See also, Benjamin Q. Huynh et al., “ Public Health Impacts of an Imminent Red Sea Oil Spill,”
Nature Sustainability, (2021), October 11, 2021, and Janelle Weaver, “ Anticipated Spill from Deteriorating Red Sea
Oil T anker T hreatens Public Health, Stanford-led Study Finds,” Stanford School of Medicine, October 11, 2021.
26 Yemen Data Project, Air War Dataset, available online at https://yemendataproject.org/data.html.
27 U.S. Department of State, T he United States Condemns Houthi Attack Against Saudi Arabia, Press Statement,
Antony J. Blinken, Secretary of State, September 5, 2021.
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Figure 4. Saudi-led Coalition Air Strikes per Month

Source: Yemen Data Project, November 2021.

Peace Efforts Stall
Throughout 2021, various third parties, including special envoys from the United Nations and
United States as wel as Omani officials, have attempted to work in concert in order to reach a
cease-fire between the Houthis and the Saudi-led coalition. These efforts have coincided with a
separate track of talks hosted by the Iraqi government between high level Saudi and Iranian
officials, reportedly aimed at deescalating regional tensions in various locales, including Yemen.28
In March 2021, Saudi Arabia offered a nationwide ceasefire that was praised by U.S. officials.29
Specifical y, Saudi Foreign Minister Prince Faisal bin Farhan proposed that, if the Houthis agreed
to a nationwide ceasefire under U.N. supervision, Saudi Arabia would (1) adhere to a U.N.-
supervised ceasefire, (2) reopen Sana'a International Airport to direct flights, (3) al ow fuel into
Hudaydah port with revenues deposited in a joint Houthi-ROYG bank account, and (4) restart
political negotiations for a permanent settlement to the conflict. The Houthis almost immediately
dismissed the Saudi proposal as “nothing new” and reiterated their demands for the Saudis
unilateral y to lift their blockade of Sana'a airport and Hudaydah port.30

28 “Iran-Saudi T alks have Gone a ‘Good Distance’ – Iran’s Foreign Minister,” Reuters, October 7, 2021.
29 U.S. Department of State, Briefing on Yemen with T imothy Lenderking, U.S. Special Envoy for Yemen; and Sarah
Charles, USAID Assistant Administrator for Humanitarian Assistance, August 9, 2021.
30 Reuters, “Houthis say nothing new in Saudi peace offer, will keep talking,” March 22, 2021.
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In late summer 2021, Swedish diplomat Hans Grundberg became the U.N. Special Envoy for
Yemen. Upon taking office, Grundberg acknowledged the difficult path toward brokering peace
in Yemen, saying “The conflict parties have not discussed a comprehensive settlement since
2016.... It is therefore long overdue for the conflict parties to engage in peaceful dialogue with
one another under U.N. facilitation on the terms of an overarching settlement, in good faith and
without preconditions.”31
As of November 2021, the Houthis have continued to demand that the coalition agree to lift
restrictions on access to airports and ports in northern Yemen prior to any ceasefire agreement.
With the Houthis continuing to advance on multiple fronts throughout Yemen, many observers
doubt that third-party mediation wil result in any diplomatic breakthroughs. According to Peter
Salisbury of the International Crisis Group, “From an Iranian perspective, their al y in Yemen the
Houthis appear very close in effect to winning the war in the north, if not the entire country. It is
extremely difficult to understand why they or the Houthis would feel this is the right moment to
stop.”32
Iranian Support to the Houthis
Iranian knowledge transfer and military aid to the Houthis, in violation of UNSCR 2216, has
increased the Houthis’ ability to threaten Saudi Arabia, other Gulf nations, and waters adjacent to
Yemen. According to the U.N. Panel of Experts on Yemen, “An increasing body of evidence
suggests that individuals or entities in the Islamic Republic of Iran supply significant volumes of
weapons and components to the Houthis.”33
The United States, the United Kingdom, Israel, and Saudi Arabia al have offered evidence
throughout 2021 of extensive Iranian military involvement in Yemen. In April 2021, Iran
acknowledged that one of its vessels in the Red Sea had been attacked. Subsequent reports
suggested that Israel may have attacked the MV Saviz, a suspected Islamic Revolutionary Guard
Corps floating base used, according to Saudi sources, to conduct surveil ance and facilitate
weapons transfers into Yemen.34 In May 2021, the U.S. Navy announced that the guided-missile
cruiser USS Monterey intercepted a stateless dhow in the northern reaches of the Arabian Sea.
After sailors boarded it, they uncovered 3,000 Chinese Type 56 assault rifles, hundreds of other
heavy machine guns, sniper rifles, and dozens of advanced, Russian-made anti-tank guided
missiles.35 In September 2021, Israel identified an Iranian base (Kashan Base north of Esfahan)
used to train foreign militants, including the Houthis, on drone technology.36 In October 2021, a

31 Edith M. Lederer, “New UN envoy: Yemen is stuck in `indefinite state of war,'” Associated Press, September 10,
2021.
32 Mohammed Ghobari and Ghaida Ghantous, “Yemen's Marib City Battens Down as Houthis Advance T hrough
Energy-Rich Province,” Reuters, November 2, 2021.
33 See United Nations Panel of Experts on Yemen, “Letter dated 22 January 2021 from the Panel of Experts on Yemen
addressed to the President of the Security Council,” U.N. Document S/2021/79, January 25, 2021.
34 Jon Gambrell, “Iran Ship said to be Red Sea T roop Base off Yemen Attacked,” Associated Press, April 7, 2021.
35 Jon Gambrell, “US Navy seizes Arms Shipment in Arabian Sea likely bound for Yemen,” Associated Press, May 9,
2021.
36 Jeremy Binnie, “Israeli Defence Minister Identifies Iran’s UAV T raining Base for Foreigners,” Jane’s Defence
Weekly, September 14, 2021.
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report prepared for the British government found that Iran has used a network of global
commercial companies to procure components for Houthi arms.37
Missile and drone attacks perpetrated by Iran and Iran-supported militant groups represent a
significant threat inside and outside of Yemen. Iran has supplied Yemen-based Houthis and other
regional proxy groups with weapons to conduct destructive and sometimes lethal attacks using
drones, missiles, and rockets against a variety of Saudi sites, including critical infrastructure,
civilian airports, military bases, and energy facilities throughout the country, as wel as vessels in
Red Sea shipping lanes. Recent attacks were aimed at targets throughout Saudi Arabia including
Riyadh, Jeddah, Dhahran, Jizan, Khamis Mushayt, the civilian airport in Abha, Al Kharj, and
military instal ations in the south, as wel as oil and gas facilities. Debris from intercepted drones
and missiles represents a recurrent risk to civilian areas and populations.38
In October 2020, Iran appointed Hassan Eyrlo (alt. sp. Irlu) as Ambassador to the so-cal ed
“National Salvation Government,” the Houthi-run northern Yemeni authority. The appointment
made Iran the first country to recognize the Houthis diplomatical y as a legitimate government
since they seized control of the capital city of Sana’a in 2014. On December 8, 2020, under the
authority of Executive Order 13224, the U.S. Department of the Treasury’s Office of Foreign
Asset Control (OFAC) designated Hassan Eyrlo as a Special y Designated National (SDN) due to
his position as an “official in Iran’s Islamic Revolutionary Guard Corps-Qods Force (IRGC-QF)
and the Iranian regime’s envoy to the Houthi rebels in Yemen.”39 Eyrlo attended a January 2021
vigil in Sana’a to mark the one-year anniversary of the U.S. kil ing of former IRGC-QF
Commander Qassem Soleimani.
Southern Yemen: Tentative Unity between the
ROYG and STC
In December 2020, the UAE-backed Southern Transitional Council (STC) formal y joined a unity
government with the ROYG, ending several years of clashes in Aden between southern
separatists and forces loyal to President Hadi. Saudi Arabia brokered the formation of the unity
government after over a year of STC-ROYG negotiations that followed the two sides’
commitment to cooperate as part of the November 2019 Riyadh Agreement. Under their unity
arrangement, the STC received several cabinet positions and agreed to redeploy their military
forces from Abyan and Aden. On December 30, 2020, as the new members of the government
landed at Aden airport to assume their posts, the Houthis launched a coordinated missile attack
against the airport, which kil ed 25 people, including three members of the International Red
Cross.40
While the UAE formal y withdrew its main military contingent from Yemen in 2019, it has
retained a smal military presence while working with proxies throughout southern Yemen, most
notably the STC. In 2021, there have been several reports al eging that the UAE, either

37 Benoit Faucon and Dion Nissenbaum, “Iranian Drones Reshape Mideast Security,” Wall Street Journal, October 7,
2021.
38 U.S. Department of State, Saudi Arabia T ravel Advisory, September 17, 2019 .
39 U.S. Department of the T reasury, “ Treasury Sanctions Iran’s Envoy in Yemen and University Facilitating
Recruitment for Qods Force,” Press Release, December 8, 2020.
40 International Committee of the Red Cross, “Yemen: T hree ICRC Staff Members Killed in Airport Blast,” December
30, 2020.
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unilateral y or through local proxies, has been constructing infrastructure or asserting influence
on the Red Sea volcanic island of Mayun and in the Socotra archipelago, both of which are
strategical y located in the Arabian Sea-Bab al Mandeb corridor.41 According to the United
Nations Panel of Experts on Yemen, “The United Arab Emirates is a member of the Coalition to
Restore Legitimacy in Yemen, yet its support to the Southern Transitional Council undermines the
Government of Yemen.”42
As the Houthis advance into Yemen’s southern provinces, such as Shabwa, home to the Balhaf
Liquefied Natural Gas Facility,43 their presence is exacerbating tensions between the STC and
ROYG.44 Fighting in Marib governorate displaced units affiliated with the Islamist political
movement Al Islah to Shabwa, placing them in close proximity to the STC, which the latter
claims is a violation of the Riyadh Agreement.45
Biden Administration Policy
After President Biden took office, one of his first foreign policy priorities was to review the
previous Administration’s recent actions on Yemen. On February 4, 2021, President Biden
announced that his Administration would increase U.S. efforts to resolve the conflict in Yemen by
(1) appointing a special envoy to Yemen; (2) ending U.S. support for offensive operations in the
war, including relevant arms sales; and (3) continuing to help Saudi Arabia defend its territory
from Houthi attacks. A week later, Secretary of State Antony Blinken revoked the previous
Administration’s January 2021 designations of the Houthis as a Foreign Terrorist Organization
(FTO) and Special y Designated Global Terrorists (SDGTs).46 The Secretary retained the
designations of three Houthi individuals as SDNs under Executive Order (E.O.) 13611.47
President Obama issued that order in 2012 to block property of persons threatening the peace,
security, or stability of Yemen. On March 2, the Biden Administration designated two additional
Houthi leaders under E.O. 13611.48
Since the President’s February 2021 policy pronouncement on Yemen, the United States has
ceased support to offensive operations by Saudi Arabia and its coalition partners and made some
changes to U.S. missile and air defense posture in Saudi Arabia. In April 2021, CENTCOM
Commander General Kenneth F. McKenzie, Jr. told one reporter that in Marib, “We’re not doing

41 For example, see Jon Gambrell, “Mysterious Air Base Being Built on Volcanic Island off Yemen,” Associated Press,
May 25, 2021; and, Quentin Muller, “UAE Wants Control of the Gulf of Aden; T ensions Mount over Yemen’s
Contested Islands,” Le Monde diplom atique, September 2021.
42 See United Nations Panel of Experts on Yemen, “Letter dated 22 January 2021 from the Panel of Experts on Yemen
addressed to the President of the Security Council,” S/2021/79, January 25, 2021.
43 Several key foreign investors are involved in natural gas production in Yemen. For Balhaf, the French company
T otal SA has a 39.6% interest alongside U.S.-based Hunt Oil (17.2%); South Korea’s SK Innovation, and Hyundai and
Kogas (a combined 21.4%).
44 In Yemen, the tribal/Sunni Islamist movement known as Al Islah (Reform) has been a major player in national
politics for decades and, since the Houthi offensive in 2014, it aligned itself with the ROYG and Saudi Arabia. In order
to counter the ROYG-Saudi-Islah alliance, the UAE chose to align itself with southern separatists.
45 “Separatists and Islamists Vie for Power in Southern Yemen,” Economist Intelligence Unit – ViewsWire, October 27,
2021.
46 U.S. Department of State, Revocation of the T errorist Design ations of Ansarallah, Press Statement, Antony J.
Blinken, Secretary Of State, February 12, 2021.
47 Ibid., U.S. Department of State, February 12, 2021.
48 U.S. Department of the T reasury, Office of Public Affairs, “T reasury Sanctions Key Military Leaders of the
Ansarallah Militia in Yemen,” Press Release, March 2, 2021.
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anything in terms of ISR (intel igence, surveil ance, and reconnaissance) … on things happening
in Marib or places like that.”49 Nevertheless, Administration officials have reiterated U.S. support
for Saudi Arabia's territorial defense. In April 2021 testimony before the House Armed Services
Committee, Amanda Dory, Acting Under Secretary of Defense for Policy, stated:
Our second line of effort is to provide limited, non-combat support to the Saudi-led
Coalition (SLC) focused on defending Saudi Arabia from external threats. This non-
combat support is consistent with President Biden's February 4, 2021 announcement to
increase U.S. diplomatic efforts to end the war in Yemen and cease U.S. support to SLC
offensive operations in Yemen. Continued U.S. assistance is designed to reassure U.S.
partners of our commitment to their defense so that they can meaningfully engage in the
United Nations political process to end the war. In support of the President's policy, roughly
60 DoD military advisors are deployed to help Saudi Arabia's Armed Forces defend their
territory from threats emanating from Yemen.50
In June 2021, President Biden reported to the Congress that:
A small number of United States military personnel are deployed to Yemen to conduct
operations against al-Qa’ida in the Arabian Peninsula and ISIS. The United States military
continues to work closely with the Government of the Republic of Yemen and regional
partner forces to degrade the terrorist threat posed by those groups. I have directed an end
to United States support for the Saudi‑led Coalition’s offensive military operations against
the Houthis in Yemen. United States Armed Forces, in a non‑combat role, continue to
provide military advice and limited information to regional forces for defensive and
training purposes only as they relate to the Saudi-led Coalition’s campaign against the
Houthis in Yemen. Such support does not involve United States Armed Forces in hostilities
with the Houthis for the purposes of the War Powers Resolution. United States Armed
Forces are deployed to the Kingdom of Saudi Arabia to protect United States forces and
interests in the region against hostile action by Iran or Iran-backed groups. These forces,
operating in coordination with the Government of the Kingdom of Saudi Arabia, provide
air and missile defense capabilities and support the operation of United States fighter
aircraft. The total number of United States forces in the Kingd om of Saudi Arabia is
approximately 2,742.51
By summer 2021, with little progress toward peace negotiations, the Biden Administration had
become more openly critical of the Houthis for rejecting repeated attempts at brokering a cease-
fire while continuing their ground offensive in Yemen and their aerial assaults against civilian
targets inside Saudi Arabia.52 Throughout 2021, the Biden Administration has continued to use its
authority to sanction individual Houthi leaders who have obstructed Yemen’s stability.53 In May
2021, the Biden Administration, pursuant to Executive Order 13611, designated two senior

49 “US-Made Drones Downed over Yemen weren't Military’s, CENT COM says,” Al Monitor, June 24, 2021.
50 T estimony of Amanda Dory, Acting Under Secretary of Defense for Policy, Department of Defense, Hearing
entitled, “ National Security Challenges and U.S. Military Activities in the Greater Middle East and Africa, ” House
Armed Services Committee, April 20, 2021.
51 T he White House, Letter to the Speaker of the House and President Pro T empore of the Senate Regarding the War
Powers Report, June 8, 2021.
52 See, U.S. Department of State, Department Press Briefing, July 1, 2021 and United States Mission to the United
Nations, Ambassador Richard Mills, U.S. Deputy Representative to the United Nations, New Y ork, NY, September 10,
2021.
53 Pursuant to, inter alia, the International Emergency Economic Powers Act (50 U.S.C. §§1701 et seq.) and the
National Emergencies Act (50 U.S.C. §§1601 et seq.). T he President has extended the national emergency declared in
Executive Order 13611 of May 16, 2012, with respect to Yemen to continue in effect beyond May 16, 2021. See,
Congressional Record, House Executive Communications, Page H2183, May 11, 2021, Continuation of the National
Emergency with Respect to Yemen--Message from the President of the United States (H. Doc. No. 117 -37).
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Houthis leaders as SDNs for their role in the offensive against Marib.54 On June 10, 2021, under
the authority of Executive Order 13224, the Treasury Department designated several members of
a smuggling network that “helps fund Iran's Islamic Revolutionary Guard Corps-Qods Force
(IRGC-QF) and the Houthis in Yemen.”55 In November 2021, the Administration designated
Saleh Mesfer Alshaer, the commander of the Houthi-controlled military logistics organization, as
an SDN for smuggling weapons and misappropriating state funds designated for hospitals.56
Houthis Storm U.S. Embassy
In early November 2021, Houthi gunmen entered the U.S. Embassy in Sana’a, where they captured 39 local
Yemeni staff who maintain the compound. The U.S. State Department and Members of Congress immediately
denounced the action and cal ed on the Houthis to release al personnel.57 According to the State Department,
“The Houthis’ unprovoked abuse of these Yemeni citizens is a gross disregard of diplomatic norms, as is the
Houthis’ flagrant breach of the compound used by the U.S. Embassy prior to 2015.”58 Several weeks later, most
employee who were kidnapped were released, though as of November 23, several remain in Houthi custody. On
February 11, 2015, due to the deteriorating security situation in Sana’a, the State Department suspended embassy
operations and U.S. Embassy staff was relocated to Saudi Arabia. Since then, the embassy has been primarily
maintained and protected by local Yemeni employees.
As of early November 2021, the Administration has continued to single out the Houthis as the
primary party responsible for perpetuating conflict. According to U.S. State Department
Spokesperson Ned Price, “The Houthis, despite their claims to the contrary, have been a primary
cause of the hardship that the people of Yemen face today. There have been credible proposals put
on the table, proposals that the Republic of Yemen Government, proposals that Saudi authorities
have also been behind that – on which the Houthis have so far been unwil ing to engage.”59
Yemen’s Humanitarian Crisis
The United Nations has described Yemen’s humanitarian crisis as currently one of the worst in
the world, with close to 80% of Yemen’s population of nearly 30 mil ion needing some form of
assistance. In Yemen, myriad factors (e.g., war, loss of health services, funding shortages,
currency depreciation) have combined to put the most vulnerable populations at risk. According
to various United Nations agencies, acute malnutrition among children under the age of five in
Yemen has hit the highest levels ever recorded; nearly 2.3 mil ion children under age 5 in Yemen
are at risk of acute malnutrition in 2021.60 Over 10,000 children have been kil ed or injured in

54 U.S. Department of the T reasury, "Treasury Sanctions Senior Houthi Military Official Overseeing Group's Offensive
Operations," press release, May 20, 2021.
55 U.S. Department of the T reasury, "Treasury Sanctions Network Financing Houthi Aggression and Instability in
Yemen," press release, June 10, 2021.
56 U.S. Department of State, Designation of Houthi Official in Yemen, Press Statement , Antony J. Blinken, Secretary of
State, November 19, 2021.
57 See, McCaul, Meeks, Risch, Menendez Joint Statement on Houthi Breach of U.S. Embassy in Yemen, Press Release,
November 12, 2021.
58 U.S. State Department, T he United States Condemns the Houthi Detention of Yemeni Staff of the U.S. Embassy in
Sana’a and Breach of Embassy Compound, Press Statement, Antony J. Blinken, Secretary of State, November 19,
2021.
59 U.S. Department of State, Department Press Briefing, November 3, 2021.
60 United Nations Office for the Coordination of Humanitarian Affairs, Yemen Situation Report, February 14, 2021.
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Yemen since 2015; currently 4 in 5 children are in need of humanitarian assistance, 400,000 are
suffering from severe acute malnutrition, and 2 mil ion are out of school.61
Food Insecurity & Humanitarian Access
While the international community has not official y declared a famine in Yemen, food insecurity
amongst large swaths of the population is widespread (see Figure 5). According to the World
Food Program in October 2021, 16.2 mil ion people are food insecure, and 47,000 face famine-
like conditions.62 While the conflict continues to be the main driver of food insecurity across the
country, a worsening economic crisis in the form of rising prices and an increasingly high
exchange rate in southern Yemen is creating additional burdens for many Yemenis.63
Humanitarian workers have long documented the numerous chal enges to working in Yemen,
such as lack of access to areas in need of assistance. As Yemen has devolved into various centers
of power, aid agencies have had to navigate competing rules and regulations between northern
and southern Yemen and sometimes within individual governorates. According to one account,
“Institutional overlap between rival governments has created numerous logistical issues, such as
humanitarian workers needing to obtain duplicate visas and permits from multiple ministries.”64
As the Houthis have become further ensconced in northern Yemen and placed key members in
positions of authority, Houthi restrictions on humanitarian aid agencies working in northern
Yemen have grown more onerous.65 Control and diversion of aid is one means Houthi forces,
Houthi partners, and other parties to the conflict have used to finance their operations.66
In 2020, as international frustration over Houthi obstruction of humanitarian assistance mounted,
the international community warned that if the Houthis do not abide by the principles of
international humanitarian law and al ow for unimpeded access for humanitarian assistance, they
wil risk losing aid. In March 2020, USAID initiated a partial suspension of its funding to support
humanitarian operations in northern Yemen. The suspension followed several weeks of warnings
from U.S. officials that the Trump Administration was extremely concerned over Houthi
obstruction of aid.67 The Biden Administration lifted the suspension in March 2021,68 and in
September announced nearly $291 mil ion in additional humanitarian assistance for Yemen as
“ongoing hostilities, a deepening economic crisis, acute food insecurity, and the spread of
COVID-19 continue to generate humanitarian needs in the country.”69

61 UN News, “ Yemen war reaches ‘shameful milestone’ - 10,000 children now killed or maimed,” October 19, 2021.
62 World Food Programme, “ Yemen Situation Report #9, September 2021,” October 18, 2021.
63 USAID, “Yemen – Complex Emergency, Fact Sheet #8, Fiscal Year (FY) 2021” September 23, 2021.
64 Jan Egeland et al., “Humanitarian Aid and the Biden Administration: Lessons from Yemen and Syria,” Policy Forum
Report , T he Washington Institute for Near East Policy, January 25, 2021.
65 According to senior U.N. officials, Houthi obstructions include: obstacles to beneficiary registration, attempts to
divert aid, efforts to control selection of implementing partners, detention and arrest of h umanitarian workers, and
intimidation and harassment of aid workers at Sanaa airport. See Under-Secretary-General for Humanitarian Affairs
and Emergency Relief Coordinator Mark Lowcock, “Briefing to the Security Council on the Humanitarian Situation in
Yemen - As Delivered,” New York, NY, September 16, 2019. See also “ UN: Houthi Rebels Impeding Aid Flow in
Yemen,” Al Jazeera English, February 19, 2020.
66 Sam Kiley, Sarah El Sirgany, and Brice Lainé, “CNN exposes systematic abuse of aid in Yemen,” CNN, May 20,
2019.
67 Ambassador Kelly Craft, “ Remarks at a U.N. Security Council Briefing on the Situation in Yemen,” U.S. Mission to
the United Nations, February 18, 2020.
68 Katrina Mason, “ US resumes aid to rebel-controlled regions of Yemen,” Financial Times, March 11, 2021.
69 USAID, “Yemen – Complex Emergency, Fact Sheet #8, Fiscal Year (FY) 2021” September 23, 2021.
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Figure 5. World Food Programme: Emergency Dashboard Yemen
August 2021

Source: World Food Programme, Yemen Emergency Dashboard August 2021, updated September 2021.
The COVID-19 Pandemic in Yemen
The COVID-19 pandemic has added an additional layer of concern for Yemen’s already depleted
health system. Data from the World Health Organization from November 2021 indicate a total of
9,806 COVID-19 cases with 1,894 deaths; most health experts believe that these figures vastly
underestimate the extent of COVID-19 in Yemen.70 Nearly 550,000 vaccine doses have been
administered in the country.71 A delivery of approximately 151,200 doses of Johnson & Johnson
COVID-19 vaccines provided by USAID through COVAX, the global COVID-19 vaccination
distribution program arrived in August 2021, as the country was beginning to witness a third
wave of cases in September-October 2021. Yemen previously received 360,000 AstraZeneca
vaccines in March through COVAX, and the United States has agreed to provide an additional
350,000 doses through COVAX. 72 The United Nations has procured medical equipment, testing
kits, and medicine while seeking additional supplies. Aid groups also have increased the capacity

70 United Nations, COVID-19 Preparedness and Response Monthly Report, December 2020.
71 World Health Organization, “COVID-19 Dashboard,” accessed November 4, 2021.
72 USAID, “Yemen – Complex Emergency, Fact Sheet #8, Fiscal Year (FY) 2021” September 23, 2021.
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of intensive care units (ICUs) in COVID-19 designated hospitals from 38 in May 2020 to 59 as of
December 2020.73
The Public Broadcasting Service’s documentary series Frontline has reported on how Houthi
authorities in northern Yemen have concealed the impact of COVID-19 in areas under their
control. According to one reporter who was permitted to visit northern Yemen in the summer of
2020, Houthi authorities “put out very little public information about the spread of COVID. But
they’ve promoted propaganda videos ... showing them mobilizing against the virus.”74 The
Houthis claim that the Saudi-led coalition’s blockade of Hudaydah and the Sana’a airport have
prevented them from procuring the supplies they need to combat the virus. Human Rights Watch
reports that Houthi authorities maintain a policy of withholding data on cases and deaths, and
continue to block vaccination efforts and spread disinformation about the virus.75
International Pledges for Yemen
On March 1, 2021, the United Nations hosted the virtual High Level Pledging Event for the
Humanitarian Crisis in Yemen. For 2021, the U.N. is seeking $3.85 bil ion for operations in
Yemen; however, donors pledged $1.7 bil ion. Secretary Blinken spoke at the event, announcing
that the United States would contribute $191 mil ion in additional assistance, bringing total U.S.
spending in FY2021 to $350 mil ion. The United States provided $630.4 mil ion in total
humanitarian aid for the crisis in Yemen in FY2020, close to the annual average U.S. al ocation
over the last four fiscal years ($644 mil ion). Secretary Blinken cal ed on other donors,
“especial y those in the region – to step up.”76 Other donations include $430 mil ion from Saudi
Arabia, $244 mil ion from Germany, and $230 mil ion from the UAE.77
Conflict Analysis
The Biden Administration has made a number of changes in U.S. Yemen policy designed to
emphasize its peacemaking role and prioritize efforts to resolve the humanitarian crisis. While the
Biden Administration lifted the Trump Administration’s terrorism designations of the Houthis,78 it
has targeted additional Houthis leaders using Yemen-specific authorities (E.O. 13611), while also
condemning Houthi attacks against civilians and Saudi Arabian territory.79 To date, the Biden
Administration has not publicly clarified what it means by its decision to no longer support
Saudi-led coalition offensive operations in Yemen, or what its defensive support to Saudi Arabia
entails.80 According to one report, U.S. officials assessed existing and potential sales of U.S.

73 United Nations, COVID-19 Preparedness and Response Monthly Report, December 2020.
74 Public Broadcasting Service, “Yemen’s COVID Cover-Up,” Frontline, February 9, 2021.
75 Human Rights Watch, “ Yemen: Houthis Risk Civilians’ Health in Covid-19,” June 1, 2021.
76 U.S. Department of State, Office of the Spokesperson, “Secretary Antony J. Blinken at the 2021 High -Level
Pledging Event for the Humanitarian Crisis in Yemen,” Remarks, March 1, 2021.
77 A complete list of donors is available online at http://www.unocha.org/sites/unocha/files/20210103-
YemenHLE2021_AnnouncementsResults.pdf.
78 U.S. Department of State, “Department Press Briefing, February 16, 2021,” Ned Price, Department Spokesperson,
February 16, 2021.
79 U.S. Department of State, Office of the Spokesperson, “Houthi Attacks Impacting Civilians,” Press Release, Ned
Price, Department Spokesperson, February 7, 2021.
80 In a recent State Department press conference, Spokesperson Ned Price stated, “ T he broader point is that for any
weapons sales or transfers [to Saudi Arabia], there is now a process in place, thanks to President Biden and his efforts
to recalibrate this relationship from the start, that will evaluate, on a case-by-case basis, proposed weapons sales and
transfers based on two criteria: our interests and our values. And that second point, that latter po int, is incredibly
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equipment and training to Saudi Arabia in order to determine what U.S. support may be
considered defensive.81
Despite these tangible and rhetorical steps, the Houthis have made significant territorial gains in
recent months and may be on the cusp of forcing the ROYG and its tribal al ies in Marib to
negotiate an orderly surrender and power-sharing agreement. If the Marib front is then pacified,
additional Houthi forces would be free to advance further southward into other governorates, such
as Shabwa, where it could threaten Yemen’s other key energy facilities, such as the Liquefied
Natural Gas Facility of Balhaf. In the view of David Schenker, a former Assistant Secretary of
State for Near Eastern Affairs, “The Houthi inclination toward a military rather than a negotiated
solution is paying off. Two years into their military campaign in Marib—a strategic governorate
named for its capital city—the rebels are on the verge of conquering both.”82
Overal , while many in the international community wish to foster a political solution to the
Yemen conflict to form a unified government with which to work to al eviate the dire
humanitarian conditions, the reality on the ground resembles a fractured state, bereft of a central
authority seen as legitimate by powerful actors, where internal and external parties seek to
maximize control over territory and scarce resources. According to the latest U.N. Panel of
Experts Report on Yemen, the war in Yemen has witnessed widespread “profiteering and control
over economic resources by individuals and entities.”83
For the Houthis, the longer they remain the de-facto authority in northern Yemen, the more their
rule becomes an accepted norm, with increased potential that such legitimacy could gain more
acceptance international y. For the STC, the war has provided them with a foreign patron in the
UAE and a degree of local autonomy not seen since before the unification of Yemen in 1990. For
Iran, its military support to the Houthis has al owed it to again demonstrate how projecting power
through proxy warfare is arguably a successful strategy for expanding its regional influence.
Final y, while the UAE may have suffered reputational damage due its conduct in the Yemen war,
the Emirates have gained influence along several Yemeni coastal port towns and islands, such as
Socotra, Mayyun, Belhaf, and Mukal a.
Leaders in Saudi Arabia, who have arguably suffered the most reputational damage over their
forces’ conduct in Yemen, may feel motivated to reduce the kingdom’s military footprint in
Yemen for a number of reasons including costs, stress on military forces and platforms, and the
prospect of improved relations with the United States. However, the Houthis, and more
specifical y their apparently deepening partnership with Iran, pose a key threat to Saudi security,
and military withdrawal seems likely to leave the Houthis’ militia and control over northern
Yemen intact. If the Houthis cannot be militarily defeated, then Saudi leaders may weigh whether
or not the kingdom should acquiesce to Houthi rule by ending its enforcement of control over air
and sea access to Yemen and negotiating a cease-fire. Alternatively, Saudi Arabia could seek to
continue to pressure the Houthis by sponsoring its own Yemeni proxies. Saudi officials also may
consider seeking additional U.S. engagement to combat objectionable Iranian intervention in
Yemen in connection with broader U.S. efforts to negotiate with Iran over its nuclear program and
regional policies.

important in this case.” See, U.S. Department of State, Department Press Briefing, March 2, 2021.
81 Patricia Zengerle and Mike Stone, “Exclusive: Biden T eam Considering a Halt to 'offensive' Arms Sales for Saudis,”
Reuters, February 26, 2021.
82 David Schenker, “Biden Needs a Plan B for Yemen if Houthis Win,” Foreign Policy, November 4, 2021.
83 United Nations Panel of Experts on Yemen, “Letter dated 22 January 2021 from the Panel of Experts on Yemen
addressed to the President of the Security Council,” U.N. Document S/2021/79, January 25, 2021..
Congressional Research Service

18

Yemen: Civil War and Regional Intervention

Author Information

Jeremy M. Sharp

Specialist in Middle Eastern Affairs

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Congressional Research Service
R43960 · VERSION 43 · UPDATED
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