Cambodia: Background and U.S. Relations

November 16, 2022 – September 11, 2023 R47311

Cambodia: Background and U.S. Relations
Updated September 11, 2023
Congressional Research Service
https://crsreports.congress.gov
R47311

Cambodia: Background and U.S. Relations

R47311
Cambodia: Background and U.S. Relations September 11, 2023
The United States was a party to the 1991 Paris Peace Agreement that formally ended
the 1979-1991 civil war in Cambodia, and has long had an interest in supporting
Thomas Lum
democratic development in the country. Between 1993, when Cambodia’s first post-war
Specialist in Asian Affairs
elections were held, and 2017, when the government banned the main opposition party,

the conduct of elections improved and civil society grew, although Hun Sen, the
country’s prime minister from 1985 to 2023, often ruled in ways observers viewed as

undemocratic. As bilateral relations improved in the late-2000s, U.S. engagement with
Cambodia expanded, and it has included foreign assistance programs, limited military assistance and
cooperation, and recovery efforts for U.S. missing-in-action (MIA) from the Vietnam War. The United
States is Cambodia’s largest export market, of which garments and footwear are the main items.
U.S. relations with Cambodia have become strained in the past decade in light of the Cambodian
government’s suppression of the political opposition and its growing embrace of the People’s Republic of
China (PRC or China). In the years leading up to the 2018 national election, the Cambodian government
placed increasing restrictions on political and social activism, civil society, free speech, and foreign-funded
democracy programs. In November 2017, the Supreme Court of Cambodia issued a ruling that dissolved
the main opposition party, the Cambodia National Rescue Party (CNRP), for “conspiring with the United
States to overthrow the government.” In the July 2023 national polls, the second general election since the
CNRP was banned, Hun Sen’s Cambodian People’s Party (CPP) won 120 of 125 seats in the National
Assembly.
Immediately following the July 2023 general election, Hun Sen announced that he would step down as
prime minister while retaining leadership of the CPP, and hand power to his son, Hun Manet, who had just
been elected to the National Assembly for the first time. In August 2023, the National Assembly endorsed
Hun Manet as the new prime minister. Little is known about the political views of Hun Manet, an army
general who served as deputy commander of the Royal Cambodian Armed Forces and joint chief of staff
prior to seeking elected office, and a graduate of West Point and New York University. According to some
observers, Hun Manet is not likely to usher in major policy changes in the near term or tackle systemic
corruption in the country, although others speculate that he and a new generation of government ministers
may provide opportunities for improved U.S.-Cambodian relations.
The U.S. government has called on the Cambodian government to respect human rights and restore
democratic elections, placed some restrictions on U.S. development assistance and suspended military
assistance, and sanctioned some Cambodian officials for corruption or human rights violations. The
Consolidated Appropriations Act, 2023 (P.L. 117-328, Sec. 7043(b)) prohibits assistance to the
Government of Cambodia unless the Secretary of State certifies that Cambodia is taking effective steps to
assert its sovereignty against interference by the PRC, including by verifiably maintaining the neutrality of
Ream Naval Base; cease violence, threats, and harassment against civil society and the political opposition
in Cambodia; and respect the rights, freedoms, and responsibilities enshrined in the 1993 Constitution of
Cambodia.
Observers have called Cambodia the Southeast Asian country upon which China exerts the greatest
influence. China has carried construction activities at Cambodia’s Ream Naval Base on the Gulf of
Thailand, although PRC and Cambodian officials have denied that they are for exclusive use by China’s
People’s Liberation Army. PRC investment and development projects have been concentrated in the city of
Sihanoukville and elsewhere along the Gulf of Thailand, including an international airport and a deep-water
seaport that some U.S. analysts say China potentially could use for military purposes.
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Cambodia: Background and U.S. Relations

U.S.-Cambodia Relations: Overview
U.S. relations with the Kingdom of Cambodia have grown strained over the last decade, as former
Prime Minister Hun Sen generated and responded to growing domestic and international criticism
by restricting civil and political rights, banning the political opposition in 2017, and embracing
the People’s Republic of China (PRC or China).1 The U.S. government has sought to remain
engaged with Cambodia while calling on the Cambodian government to restore political rights to
opposition politicians, providing support to Cambodian civil society, and applying pressure
through sanctions on some Cambodian officials and some restrictions on development and
military assistance.2 Areas of U.S. engagement include development aid, countering trafficking in
persons, demining assistance, U.S. POW/MIA accounting, and peacekeeping.3
President Joe Biden met with then-Prime Minister Hun Sen in November 2022 at the Association
of Southeast Asian Nations (ASEAN) summit in Phnom Penh, where he pressed the Cambodian
leader to release political activists and to “reopen civic and political space” ahead of the July
2023 national election, and expressed concerns about PRC construction activities at Cambodia’s
Ream Naval Base.4 In the national election held on July 23, 2023, Hun Sen’s Cambodian People’s
Party (CPP), which faced little competition due to its suppression of opposition groups, won a
“landslide victory.”5 The State Department released a statement declaring, “The United States is
troubled that the July 23 Cambodian national elections were neither free nor fair.” The statement
continued, “In response, the United States has taken steps to impose visa restrictions on
individuals who undermined democracy and implemented a pause of certain foreign assistance
programs.”6
In December 2021, the CPP reportedly endorsed West Point graduate Hun Manet, the eldest son
of Hun Sen, as his successor.7 Immediately following the July 2023 general election, Hun Sen
announced that he would step down as prime minister while retaining leadership of the CPP, and
hand power to Hun Manet, who had just been elected to the National Assembly for the first time.8
In August 2023, the CPP-dominated National Assembly endorsed Hun Manet as the new prime
minister. Little is known about the political views of Hun Manet, an army general who served as
deputy commander of the Royal Cambodian Armed Forces and joint chief of staff prior to
seeking elected office. Some observers do not expect Hun Manet, a graduate of West Point and
New York University, to usher in major policy changes in the near term, nor to tackle systemic
corruption in the country.9 Others speculate that the new prime minister, as well as the possibility

1 For brief background on Cambodia, see CRS In Focus IF10238, Cambodia, by Thomas Lum.
2 Congresswoman Aumua Amata Coleman Radewagen, “Delegation Focuses on Rights and Freedom in Cambodia,”
press release, August 19, 2022.
3 Department of State, “The United States-Cambodia Relationship,” fact sheet, November 12, 2022.
4 The White House, “Readout of President Joe Biden’s Meeting with Prime Minister Hun Sen of Cambodia,”
November 12, 2022.
5 Prak Chan Thul, “Cambodia PM’s Party Claims Landslide Election Win Ahead of Historic Transition,” Reuters, July
23, 2023.
6 Department of State, “National Elections in Cambodia,” press statement, July 23, 2023.
7 Sorn Sarath, “CPP Officially Backs Hun Manet to be Next Prime Minister,” Cambodia Journalists Alliance
Association News, December 24, 2021.
8 “Cambodia’s Hun Sen, One of World’s Longest-Serving Leaders, to Hand Power to Son,” Reuters, July 26, 2023.
9 Sui-Lee Wee, “A ‘Once-in-a-Lifetime’ Change in Cambodia: A New Leader,” New York Times, August 21, 2023;
Armani Syed, “What to Know About the Army Chief Who Will Be Cambodia’s Next Leader,” Time, July 26, 2023;
“Hun Sen’s Party Claims a Win in Cambodian Election After Opposition Was Suppressed,” Associated Press, July 23,
2023.
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of new, younger cabinet appointees, may alter the tone of Cambodia’s relations with the United
States and the West and set the stage for greater mutual engagement.10
U.S. Interests
The United States, which was a party to the 1991 Paris Peace Agreements on Cambodia, has
sought to influence Cambodia’s political development and, with the help of the United Nations,
helped establish Cambodian democratic institutions.11 Given China’s growing economic and
strategic engagement in the Indo-Pacific, particularly during the past decade and a half, U.S.
policies have aimed to help strengthen Cambodia’s economy and civil society while providing
disincentives for the kingdom to align with China. The U.S. government has aimed to support
these objectives through support for trade, development assistance, and limited engagement with
Cambodian military and security services.12 In 2017, the Cambodian government suspended
Angkor Sentinel, an annual bilateral military exercise launched in 2010 that focused on
international peacekeeping, humanitarian assistance, and military-to-military cooperation. Some
observers interpreted the unilateral action as a sign that Hun Sen was distancing Cambodia from
the United States as the U.S. government was becoming more critical of his policies.13
Policy Actions
Congress periodically has imposed conditions upon some U.S. assistance to Cambodia in order to
promote democracy and human rights in the kingdom. From 1998 to 2007, Congress prohibited
government-to-government assistance to Cambodia to pressure Hun Sen into fully instituting
democracy, but allowed U.S. assistance to nongovernmental organizations (NGOs) and some
humanitarian programs to continue. Congress lifted the ban in 2007 due in part to improving
democratic processes, although most U.S. assistance efforts in Cambodia continued to be
channeled through NGOs.
Since FY2017, State, Foreign Operations, and Related Programs Appropriations (SFOPS)
legislation have placed conditions upon some U.S. assistance to Cambodia due to human rights
and other concerns. The Consolidated Appropriations Act, 2023 (P.L. 117-328, Sec. 7043(b))
prohibits assistance to the Government of Cambodia unless the Secretary of State certifies that
Cambodia is taking effective steps to assert its sovereignty against interference by the PRC,
including by verifiably maintaining the neutrality of Ream Naval Base; cease violence, threats,
and harassment against civil society and the political opposition in Cambodia; and respect the
rights, freedoms, and responsibilities enshrined in the 1993 Constitution of Cambodia, among
other provisions. The Asia Reassurance Initiative Act also imposed democracy-related and other
conditions upon U.S. assistance to the government of Cambodia.14

10 Samban Chandara, “Manet Seeks Out ‘Mutual Respect’ in US Relationship,” Phnom Penh Post, August 30, 2023;
David Hutt, “Will Hun Manet Reset Ties with the West?” Asia Times, July 25, 2023.
11 United Nations, “Cambodia—20 Years on from the Paris Peace Agreements,” October 21, 2011. The Paris Peace
Agreement formally ended over two decades of armed conflict in Cambodia.
12 Department of State, “Integrated Country Strategy: Cambodia,” March 22, 2022.
13 “Cambodia’s Decision to Nix Military Exercises with US Leaves Many Scratching Their Heads,” Southeast Asia
Globe, January 19, 2017; Angkor Sentinel, GlobalSecurity.org, at https://www.globalsecurity.org/military/ops/angkor-
sentinel.htm.
14 P.L. 115-409, Title II, §201(b).
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In 2018, the U.S. government suspended International Military Education and Training (IMET)
programs in Cambodia in response to the government’s suppression of the political opposition.15
Prior to the suspension, IMET programs had aimed to “help Cambodia’s military become better
equipped to address transnational and global threats, support and sustain democratic institutions,
respond to humanitarian crises, and ensure the safety of U.S. citizens visiting or living in
Cambodia.”16 Relatedly, in 2021, the Department of Commerce and the Department of State
imposed export controls on U.S. national security-controlled items and arms to Cambodia.17 A bill
introduced in the 118th Congress, the Cambodia Democracy and Human Rights Act of 2023 (H.R.
4659 and S. 2331), would seek to promote free and fair elections, democracy, political freedoms,
and human rights in Cambodia.
The U.S. government has sanctioned five Cambodian officials since 2018, and in some cases
members of their immediate families, for corruption or human rights abuses pursuant to
Executive Order (E.O.) 13818, which implements the Global Magnitsky Human Rights
Accountability Act; three of the five Cambodian officials were also sanctioned under the SFOPS
Section 7031(c) visa restrictions authority. Specifically, the U.S. government sanctioned four
officials for corruption and one official, General Hing Bun Hieng, commander of Hun Sen’s
bodyguard unit, “for being the leader of an entity involved in serious human rights abuse.”18 In
addition, in 2020, the U.S. government sanctioned a PRC company in Cambodia, Union
Development Group (UDG), pursuant to the Global Magnitsky Act. The Treasury Department
stated that China “has used UDG’s projects in Cambodia to advance PRC ambitions to project
power globally,” that UDG activities were damaging the environment and hurting the livelihoods
of local communities, and that its infrastructure development at Dara Sakor “could be converted
to host military assets.”19
Congressional Considerations
Congress may consider various policy approaches and options related to the U.S.-Cambodia
relationship and U.S. objectives in the kingdom, including the pros and cons of supporting greater
engagement, placing sanctions on additional Cambodian officials, imposing trade sanctions,
and/or further restricting foreign assistance to the kingdom. One analyst suggests that both
Western foreign aid and sanctions have had some, albeit limited, influence, and that such leverage
has declined as China has offered an alternative development model and source of assistance.20
While Hun Manet’s intentions are unclear at this point, reports suggest he may both welcome
renewed U.S. engagement and follow in the path of his father.21 According to some analysts,
former Prime Minister Hun Sen likely sought to balance China’s growing political and economic

15 The White House, “Statement from the Press Secretary on Reduction in Assistance to the Government of
Cambodia,” February 27, 2018. The suspension is still in effect.
16 Department of State, Congressional Budget Justification, Foreign Operations, Appendix 2, FY2017.
17 U.S. Department of Commerce, “Commerce Adds Export Controls on Cambodia to Address Corruption, Human
Rights Abuses, and Regional Security Concerns,” December 9, 2021; “Revision of Controls for Cambodia Under the
Export Administration Regulations,” Federal Register, December 9, 2021; “International Traffic in Arms Regulations:
Addition of Cambodia to List of Proscribed Countries,” Federal Register, December 9, 2021.
18 Department of the Treasury, “Designations Represent Latest Efforts to Isolate Serious Human Rights Abusers and
Corrupt Actors from the US. Financial System,” June 12, 2018; Department of the Treasury, “Treasury Sanctions
Corruption and Material Support Networks,” December 9, 2019; Department of the Treasury, “Treasury Targets
Corrupt Military Officials in Cambodia,” November 10, 2021.
19 Department of the Treasury, “Treasury Sanctions Chinese Entity in Cambodia Under Global Magnitsky Authority,”
September 15, 2020.
20 Sebastian Strangio, “Cambodia Becomes the World’s Newest One-Party State,” Foreign Policy, November 17, 2017.
21 Sui-Lee Wee, “A ‘Once-in-a-Lifetime’ Change in Cambodia: A New Leader.”
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influence with that of the United States and other countries, and welcomed U.S. investment, in
particular.22 U.S. governmental and business groups may consider building upon Hun Manet’s
military and educational experiences in the United States to help strengthen bilateral relations.23
Some policy experts and Members of Congress have advocated imposing visa and economic
sanctions on Cambodian officials to pressure the Cambodian government into reversing its
suppression of democracy.24 Congress also may consider potential benefits and costs of imposing
trade sanctions, such as suspending preferential trade treatment or eligibility for the U.S.
Generalized System of Preferences (GSP) program, if it is renewed.25 In 2020, the European
Union (EU) partially suspended trade preferences for Cambodia citing human rights concerns; the
suspension affected 20% of Cambodian exports to the EU.26 Some analysts have questioned the
effectiveness of EU trade sanctions in obtaining desired political outcomes in Cambodia.27 Some
suggest that U.S. punitive actions may encourage Cambodia to seek even closer relations with
China.28 Furthermore, some state that trade penalties hurt ordinary Cambodians, particularly
garment workers and their families.29
Congress may consider the pros and cons of supporting various kinds of engagement, much of
which might be funded through SFOPS legislation. Some commentators argue that greater U.S.
engagement in Cambodia would help further U.S. interests by garnering influence, soft power,
and/or goodwill. They state that the United States could further its aims in Cambodia through
expanded and well-publicized development assistance, greater funding for Khmer language Voice

22 Charles Dunst, “Hun Sen, Marcos, and the Anatomy of an American Smile,” Center for Strategic and International
Studies, August 18, 2022; “Cambodia Hails US Ties, Seeks Relief on China-Linked Sanctions,” Bloomberg, May 26,
2022; Chanoutdam, “PM Hun Sen Supports US Investment in Cambodia,” Eacnews.asia, May 5, 2022; Sao Phal
Niseiy, “US Engagement with Cambodia Needs to Move Beyond the ‘China Factor’,” The Diplomat, June 4, 2021.
23 Simon Lewis and David Brunnstrom, “Hun Sen Heir Could Get New York Business Reception after Cambodia
Succession,” Reuters, August 4, 2024.
24 The Cambodia Democracy Act of 2018 (H.R. 5754, passed in the House), Cambodia
Democracy Act of 2019 (H.R. 526, passed in the House, and S. 3081), Cambodia Democracy Act
of 2021 (H.R. 4648, passed in the House), Cambodia Democracy and Human Rights Act of 2022
(S. 3052), and Cambodia Democracy and Human Rights Act of 2023 (H.R. 4659 and S. 2331)
would block the assets and restrict the entry of senior Cambodian officials determined to have
substantially undermined democracy in Cambodia. See also Claudio Francavilla, “EU Should
Sanction Cambodia’s ‘Dirty Dozen,’” Human Rights Watch, March 15, 2021; Olivia Enos,
“Holding Cambodia Accountable for Its Descent into One-Party Rule,” The Heritage Foundation
Issue Brief No. 4894, August 7, 2018; House Committee on Foreign Affairs, Subcommittee on
Asia and the Pacific, “Cambodia’s Descent: Policies to Support Democracy and Human Rights in
Cambodia,” December 12, 2017.
25 The GSP program expired on December 31, 2020, and Congress has not reauthorized it. The GSP program grants
duty-free treatment on some Cambodian exports to the United States. In general, the GSP program includes Cambodian
export items such as handbags and travel goods, but excludes textiles, apparel, and footwear, which are among
Cambodia’s top export items.
26 European Commission, “Cambodia Loses Duty-Free Access to the EU Market over Human Rights Concerns,”
August 12, 2020.
27 David Hutt, “Do EU Sanctions on Cambodia Still Matter?” The Diplomat, July 3, 2020.
28 Sebastian Strangio, “US House of Representatives Passes Cambodia Sanctions Bill,” The Diplomat, September 30,
2021; Tomoya Onishi, “Cambodia Drawn Ever Closer to China a Year after EU Sanctions,” Nikkei Asia, August 13,
2021.
29 Gregory Poling and Charles Dunst, “Pariah or Partner? Clarifying the U.S. Approach to Cambodia,” Center for
Strategic and International Studies,” June 14, 2022; Kongkea Chhoeun, “Should Western Countries Impose Sanctions
on Cambodia?” Asia Times, September 14, 2017.
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of America and Radio Free Asia broadcasting, and public diplomacy efforts.30 Some observers
suggest that Cambodian civil society, independent journalists, and democratic-minded urban
youth would be particularly receptive to greater U.S. engagement.31
Cambodia’s Political Evolution
Hun Sen led Cambodia for 38 years, including as Premier of the Vietnam-backed Republic of
Kampuchea between 1985 and 1993 and during a period of “co-premiership” (1993-1997).32
Since 1993, he has headed the Cambodian People’s Party (CPP). Between 1993, when the United
Nations administered Cambodia’s first national election since the 1991 Paris Peace Agreements,
and 2017, when the Cambodian government banned the main opposition Cambodian National
Rescue Party (CNRP), democratic institutions and practices had gradually developed to allow
widespread civic and political participation, and Cambodia had developed a vibrant civil society
and a relatively free print media.33 Meanwhile, Hun Sen and the CPP employed a variety of
means to stay in power, including through electoral victories; legal and extralegal political
maneuvers; influence over the judiciary, broadcast media, and labor unions; patronage; cronyism;
violence; and intimidation.34
The CNRP made significant gains in the 2013 parliamentary election and 2017 local elections for
commune councilors. Although human rights groups reported CPP domination of the media and
government threats and intimidation against opposition parties and their supporters in the run-up
to the polls, some experts reported fewer irregularities in 2017 as compared to previous
elections.35 The CNRP’s growing electoral strength reflected the will of a younger and more
globalized electorate that was less focused on Cambodia’s past turbulence, more concerned about
corruption and inequality, and more demanding about government accountability and
performance, according to some observers.36
In November 2017, the Supreme Court of Cambodia, allegedly at the behest of the government,
issued a ruling that dissolved the CNRP for “conspiring with the United States to overthrow the
government.”37 With the CNRP banned from participating, the CPP won all 125 seats in the
National Assembly in the 2018 general election. In October 2022, a Cambodian court sentenced
former CNRP President Sam Rainsy in absentia to life in prison, on top of previous sentences of
numerous crimes that many observers view as politically motivated.38

30 Gregory Poling and Charles Dunst, “Pariah or Partner? Clarifying the U.S. Approach to Cambodia.”
31 Ibid.; Sao Phal Niseiy, “US Engagement with Cambodia Needs to Move Beyond the ‘China Factor’;” Prak Chan
Thul, “U.S. Turns to Music in Bid to Woo Cambodians,” Reuters, March 7, 2018; Julia Wallace, “As Demographics in
Cambodia Shift, Youth Seek Political Change,” New York Times, February 17, 2016.
32 Hun Sen and Norodom Ranariddh, second son of King Norodom Sihanouk, served as co-premiers between 1993 and
1997 as part of a power sharing agreement between the CPP and the FUNCINPEC Party.
33 Chak Sopheap, “Standing with Civil Society in Cambodia,” Phnom Penh Post, May 11, 2016; Sebastian Strangio,
“In Cambodia, Everything Is Different but Nothing Has Changed,” Asian Review, October 31, 2016.
34 Sebastian Strangio, “The House That Hun Sen Built,” Foreign Policy, January 13, 2015.
35 “Cambodia: Commune Elections Not Free or Fair,” Human Rights Watch, June 12, 2017; Sun Narin, “How
Cambodia’s 2017 Commune Elections Were a Turning Point for Democracy,” Voice of America, May 16, 2022.
36 See, for example, Julia Wallace, “As Demographics in Cambodia Shift, Youth Seek Political Change,” New York
Times, February 17, 2016.
37 Joshua Berlinger, “Cambodia Court Orders Main Opposition Party to Dissolve,” CNN, November 17, 2017;
Sebastian Strangio, “Cambodia’s Crumbling Democracy,” Foreign Affairs, September 14, 2017.
38 Sam Rainsy lives in self-imposed exile in France.
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Figure 1. Cambodia at a Glance

Area: 69,898 sq. miles (about the size of Missouri)
Capital: Phnom Penh
Population: 16.9 mil ion (2023 est.)
Government: Parliamentary under a constitutional monarchy
Economic Sectors: (percentage of GDP): agriculture (25); industry (33); services (42) (2017)
Life Expectancy: 71 years (2023)
Religion: Theravada Buddhism (95% of population)
Literacy: 84% (2021)
GDP per capita: $4,400 (purchasing power parity) (2021)
Source: Map created by CRS. Fact information from CIA, The World Factbook, June 16, 2023.
In April 2023, a Cambodian court convicted former CNRP Vice-President Kem Sokha of treason
and sentenced him to 27 years of house arrest. The Department of State issued a statement
asserting, “Kem Sokha’s conviction is part of a larger pattern of threats, harassment, and other
unacceptable actions by Cambodian authorities to target political opposition leaders, media, and
civil society.”39 Since 2021, Cambodian courts have convicted over 100 former CNRP politicians
and opposition activists of crimes against the state, including Cambodian-American human rights
activist and lawyer Theary Seng.40
The Candlelight Party, founded in 1995 as the Khmer Nation Party and renamed the Sam Rainsy
Party in 1997, won 18% of commune council seats in the June 2022 local elections while the CPP
won 80%.41 Prior to the July 2023 national election, some analysts viewed the Candlelight Party

39 Department of State, “On the Conviction of Kem Sokha,” press statement, March 3, 2023.
40 Seng is serving a six-year sentence for conspiracy and incitement of social disorder. Sopheng Cheang and Grant
Peck, “Cambodian Opposition Leader Gets 27 Years on Treason Charge,” San Diego Tribune, March 3, 2023;
American Bar Association, “Trial Observation Report: Cambodia v. Theary Seng,” September 15, 2022.
41 The Sam Rainsy Party merged with the Human Rights Party in 2012 to form the Cambodian National Rescue Party.
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as a fledgling opposition force.42 In May 2023, Cambodia’s Constitutional Council upheld a
decision by the National Election Committee that barred the Candlelight Party from participating
in the national election for failing to provide proper registration documents, which some outside
observers described as a politically-motivated move.43 In the July 2023 national election, the CPP
won 120 of 125 National Assembly seats.44 The royalist Party, FUNCINPEC,45 won five seats.
(See textbox, “Modern Political History of Cambodia,” below.)
Modern Political History of Cambodia
The Kingdom of Cambodia became independent from France in 1953. Beginning in 1969, during the Vietnam War,
the United States conducted a four-year, sustained, large-scale bombing campaign and incursion into officially
neutral Cambodia, aimed at stopping the flow of North Vietnamese soldiers and supplies into South Vietnam.
According to some historians, the U.S. bombing helped the Communist Party of Kampuchea (Khmer Rouge) gain
fol owers and military recruits in rural areas. In March 1970, the military forces of pro-American General Lon Nol
overthrew the government of Prince Norodom Sihanouk in a military coup. A civil war fol owed, culminating in
Lon Nol’s defeat in April 1975 by Khmer Rouge forces and the founding of “Democratic Kampuchea.”
The Khmer Rouge attempted to create an agrarian, communist society, a policy that included the forced
depopulation of cities, establishment of rural communes, and executions of many educated and wealthy
Cambodians and ethnic minorities. During its brutal three-year reign, roughly 2 mil ion out of a population of 8
mil ion Cambodians died from execution, torture, overwork, starvation, and disease.
In January 1979, Vietnamese forces drove the Khmer Rouge from Phnom Penh. A 13-year internecine war ensued,
in which an uneasy coalition of Khmer Rouge, Cambodian nationalists, and royalist insurgents, with assistance from
China, fought the Vietnamese-backed Peoples Republic of Kampuchea (PRK). Hun Sen, a former Khmer Rouge
military officer who had defected from the regime in 1977 and fled to Vietnam, served as Prime Minister and
Foreign Minister of the PRK. Fol owing the Vietnamese withdrawal from Cambodia in 1989, a United Nations
(U.N.)-brokered peace settlement, also known as the Paris Peace Agreements, officially ended the war in October
1991.
In 1993, the United Nations administered elections for a 120-seat Constituent Assembly and Prince Sihanouk
returned to Cambodia and was crowned King. For a decade and a half, three major political parties vied for power
and influence: the Cambodian People's Party (CPP) under the leadership of Hun Sen; the royalist FUNCINPEC
Party, led by Sihanouk’s second son, Norodom Ranariddh; and the eponymous opposition Sam Rainsy Party. After
four years of cooperating with FUNCINPEC under a power-sharing agreement, Hun Sen staged an armed
takeover of government in 1997. In the face of considerable international pressure and the withholding of foreign
aid, Hun Sen held new parliamentary elections in July 1998, which the CPP narrowly won. The CPP and
FUNCINPEC again agreed to form a coalition government, with Hun Sen as Prime Minister and Norodom
Ranariddh as President of the National Assembly. This uneasy partnership continued until 2006, when Ranariddh
was ousted as the leader of FUNCINPEC, which began to decline as a major political force in Cambodia.
In 2004, King Norodom Sihanouk abdicated the throne due to il ness and his eldest son, Norodom Sihamoni,
succeeded him as King. Norodom Sihanouk died of heart failure, at the age of 89, in Beijing, China, in 2012.
Restrictions on Civil Society
The Cambodian government has clamped down on civil society, the media, and some foreign-led
democracy promotion efforts. The National Assembly passed a restrictive new NGO law in 2015,
and in 2017 the Cambodian Foreign Ministry used that law to expel the Washington, D.C.-based

42 David Hutt, “Putting a Positive Spin on Cambodia’s Local Election,” The Diplomat, June 9, 2022; Eugene Whong,
“Opposition Candlelight Party Gains Steam in Cambodia in Shadow of Crackdown,” Radio Free Asia, February 7,
2022.
43 Frances Mao, “Cambodia: Opposition Candlelight Party Barred from July Vote,” BBC News, May 15, 2023.
44 Sopheng Cheang and David Rising, “US Announces Punitive Measures over Concerns That Cambodia’s Elections
Were ‘Neither Free nor Fair.’”
45 Front Uni National Pour Un Cambodge Indépendant, Neutre, Pacifique Et Coopératif. “Hun Sen’s Party Claims a
Win in Cambodian Election After Opposition Was Suppressed,” Associated Press, July 23, 2023.
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National Democratic Institute (NDI),46 which was engaged in democracy promotion programs in
Cambodia, on the grounds that NDI was not registered with the government. Cambodian
government media outlets also alleged that NDI, which received financial support through the
U.S. Agency for International Development (USAID), was involved in a conspiracy involving the
CNRP and U.S.-funded NGOs to overthrow the government.47 Roughly 25 human rights NGOs
still operate in Cambodia, although they face increasing repression. Cambodian law provides for
the right of private-sector workers to form and join independent trade unions, to bargain
collectively, and to strike. According to the Department of State, many employers place “severe
restrictions” on the formation of unions.48
Reporters Without Borders ranked Cambodia 147nd out of 180 countries in its 2023 World Press
Freedom Index, down from 132nd in 2017.49 The government restricts freedom of expression and
the press in various ways, including through defamation lawsuits, criminal prosecutions, taxation,
and occasional violent attacks on journalists. It also wields control over the media through the
approval of permits and licenses for journalists and private media outlets.50 In 2017, the
Cambodian government closed more than one dozen radio stations that sold airtime to Voice of
America (VOA) and Radio Free Asia (RFA). RFA, facing political and economic pressure from
the government, closed its Phnom Penh office.51
Authorities also ordered the English-language Cambodia Daily, known as an opposition
newspaper, to shut down in 2017, ostensibly for failing to pay taxes.52 According to some
observers, the 2018 sale of the Phnom Penh Post, another major English language daily, to a
Malaysian businessman with ties to Hun Sen, represented a final blow for established
independent journalism in the kingdom.53 In 2023, the government revoked the media license of
Voice of Democracy, a local radio and online media outlet that had reported on human rights
issues, for “disseminating false information.”54
Cambodian Economy
Since the early 1990s, Cambodia, one of the poorest countries in East Asia, has made significant
progress on some socioeconomic indicators, although poverty and malnutrition in rural areas
persist. The kingdom’s economy, which largely was destroyed by the Khmer Rouge (1975-1979)
and subsequent conflicts, achieved an average annual growth rate of 7.7% between 1998 and
2019.55 In 2020 and 2021, the COVID-19 pandemic adversely affected major sectors of the
economy, including manufacturing, construction, and tourism. The garment sector—which is
largely run by companies from China, Hong Kong, and Taiwan—forms a pillar of Cambodia’s
economy, employing roughly one million workers, predominantly women. The Economist

46 NDI is a “core institute” of the U.S.-funded National Endowment for Democracy.
47 “Ananth Baliga, “Breaking: NDI to Be Shuttered, Foreign Staff Expelled,” Phnom Penh Post, August 23, 2017.
48 Department of State, 2022 Country Reports on Human Rights Practices: Cambodia, March 20, 2023.
49 Reporters Without Borders, “Cambodia,” at https://rsf.org/en/country/cambodia.
50 Department of State, 2022 Country Reports on Human Rights Practices: Cambodia; Sun Narin, “More Than 70
Journalists Harassed in Cambodia in 2020, Report Finds,” Voice of America, April 1, 2021.
51 Ananth Baliga, Mech Dara and Niem Chheng, “RFA Shuts Down Cambodia Operations amid Media Crackdown,”
Phnom Penh Post, September 12, 2017.
52 Kevin Ponniah, “Cambodia Leader Tells Critics to Pay Up, or Pack Up,” BBC News, August 24, 2017.
53 “Phnom Penh Post: Firing and Resignations after Sale of Cambodian Daily,” BBC News, May 7, 2018.
54 “Cambodian Leader Orders Shutdown of Independent Media Outlet Voice of Democracy,” The Straits Times,
February 12, 2023.
55 World Bank, “The World Bank in Cambodia,” April 12, 2023.
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Intelligence Unit reported that garments and footwear accounted for 54.8% of Cambodian goods
exports in 2022.56 The garment sector has begun to experience some factory closures due in part
to rising labor costs, competition from other countries, weak transportation links, and low
education levels among the population.57
The United States is Cambodia’s second-largest trading partner after China, and its largest export
market, purchasing 44% of Cambodia’s exports in 2022.58 Cambodian exports to the United
States totaled $12.2 billion in 2022, while imports from the United States totaled $446 million.59
The largest Cambodian export items to the United States are apparel and leather goods, and the
largest import items from the United States are vehicles.60 The United States and Cambodia meet
regularly to discuss bilateral economic relations under the 2006 Trade and Investment Framework
Agreement (TIFA).61 In May 2022, the ASEAN Business Council organized a delegation of U.S.
companies to meet with Cambodian officials to discuss expanding U.S.-Cambodian trade and
investment ties.62
Better Factories Cambodia
Since 2001, the U.S. government has supported an International Labor Organization-led program, Better Factories
Cambodia, which monitors and works to improve labor practices in the kingdom. The program’s funding sources
have included USAID, the U.S. Department of Labor, the World Bank, Government of Cambodia, Garment
Manufacturers' Association in Cambodia, other foreign governments, and international buyers. Nearly 600
Cambodian factories reportedly participate in the program.63
Cambodia was among the top beneficiaries of the U.S. Generalized System of Preferences (GSP)
duty free trade program, which expired in 2020. The GSP program, which has not been
reauthorized by Congress, does not include preferential treatment for garments and footwear
products, so its impact on total Cambodian exports has been limited.64 In 2020, the EU partially
suspended trade preferences for Cambodia under its “Everything but Arms” (EBA) trade
program, citing concerns about political repression and human rights conditions in Cambodia.65
In 2022, The EU accounted for 17% of Cambodian exports.66

56 Economist Intelligence Unit, “Country Report: Cambodia,” July 10, 2023.
57 Economist Intelligence Unit, “Cambodia’s Textile Sector Faces Competitiveness Issues,” September 9, 2022.
58 Economist Intelligence Unit, “Country Report: Cambodia,” July 10, 2023.
59 Trade Data Monitor.
60 Ibid.
61 Office of the United States Trade Representative, “Cambodia,” at https://ustr.gov/countries-regions/southeast-asia-
pacific/Cambodia-.
62 “US-ASEAN Business Council Brings Business Delegation to Cambodia during its Chairmanship Year of ASEAN,”
U.S.-ASEAN Business Council, May 9, 2022.
63 Better Work, “Better Factories Cambodia,” at https://stage.betterwork.org/cambodia/; U.S. Department of Labor,
Bureau of International Labor Affairs, “Better Factories Cambodia,” at https://www.dol.gov/agencies/ilab/better-
factories-cambodia; Department of State, “The United States-Cambodia Relationship,” fact sheet, August 2, 2022.
64 For further information on the GSP program, see CRS Report RL33663, Generalized System of Preferences (GSP):
Overview and Issues for Congress, by Liana Wong.
65 The suspension affected selected Cambodian garment and footwear products and all travel goods and sugar,
amounting to roughly one-fifth of Cambodia’s annual exports to the EU. European Commission, “Trade/Human
Rights: Commission Decides to Partially Withdraw Cambodia’s Preferential Access to the EU Market,” February 12,
2020; Leonie Kijewski, “EU to Suspend Some of Cambodia Trade Benefits over Human Rights,” Al Jazeera, February
11, 2020.
66 Economist Intelligence Unit, “Country Report: Cambodia,” July 10, 2023.
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Cambodia acceded to the World Trade Organization in 2004, and is a member of the ASEAN Free
Trade Area. Analysts expect Cambodia to benefit from its participation in the Regional
Comprehensive Economic Partnership (RCEP), a 2020 trade pact that includes the 10 ASEAN
member states and six other Indo-Pacific countries, including China.67
U.S. and Other Foreign Assistance
Postwar Cambodia has relied heavily on foreign assistance, which accounts for 20%-25% of the
Cambodian government’s budget.68 Official Development Assistance (ODA) to Cambodia from
Organization for Economic Cooperation and Development (OECD) member countries and
international financial institutions totaled $1.0 billion in 2021; the largest providers were the
Japan, the Asian Development Bank, France, the EU, and the United States.69 The State
Department allocated an estimated $98 million in foreign assistance to Cambodia in FY2023.70
Major program areas include preventing child and maternal death and combating infectious
diseases; advancing human rights and democracy; promoting inclusive and sustainable economic
growth; improving natural resources management; and combating human trafficking.71 (See
textbox, “Human Trafficking,” below.)
Human Trafficking
Cambodia was downgraded to Tier 3 in the Department of State’s 2022 assessment and remained in that category
in 2023. The State Department’s 2023 Trafficking in Persons Report: Cambodia, stated, “The Government of
Cambodia does not ful y meet the minimum standards for the elimination of trafficking and is not making
significant efforts to do so, even considering the impact of the COVID-19 pandemic, if any, on its anti-trafficking
capacity.” The report added, “Despite the lack of significant efforts, the government took some steps to address
trafficking.”72 Trafficked persons include Cambodians who migrate to other countries for work and foreign
laborers working on construction sites and cyber scam operations run by PRC crime syndicates in Cambodia. Tier
3 countries may be subject to restrictions on certain types of foreign aid.73
Between 1993 and 2022, the U.S. government contributed approximately $192 million for
unexploded ordnance (UXO) removal and disposal, related educational and government capacity
efforts, and survivor assistance programs in Cambodia.74 Cambodia is among the countries most
heavily contaminated by UXO, including cluster munitions, landmines, and other undetonated
weapons left from U.S. bombing during the Vietnam War, the Vietnamese invasion of Cambodia
in 1978, and civil wars during the 1970s and 1980s.75 There were 64,920 known UXO casualties

67 RCEP took effect in January 2022.
68 Department of State, “U.S. Relations with Cambodia,” July 16, 2021.
69 OECD, Creditor Reporting System, at https://stats.oecd.org/index.aspx?DataSetCode=CRS1; OECD, “Aid at a
Glance Charts: Cambodia.”
70 Department of State budget documents. Congress directed not less than $82.5 million in FY2023 assistance for
Cambodia. Department of State. Consolidated Appropriations Act, FY2023 (P.L. 117-328, Sec. 7043(b)).
71 Department of State, FY2024 Congressional Budget Justification, Foreign Operations, Appendix 2.
72 Department of State, “2023 Trafficking in Persons Report: Cambodia,” June 28, 2023.
73 For further information on U.S. policy related to trafficking in persons, see CRS In Focus IF10587, Human
Trafficking and U.S. Foreign Policy: An Introduction, by Michael A. Weber.
74 Department of State, To Walk the Earth in Safety, 22st Edition, Fiscal Year 2022, April 4, 2023. These activities are
carried out largely by U.S. and international NGOs in collaboration with the Cambodian Mine Action Center, a
Cambodian NGO, and the Cambodian government.
75 For further information, see CRS Report R45749, War Legacy Issues in Southeast Asia: Unexploded Ordnance
(UXO), coordinated by Michael F. Martin.
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in Cambodia between 1979 and 2020, including 45,123 injured and 19,797 killed.76 About half of
the land contaminated with UXO reportedly has been cleared; most of the remaining land lies in
the rural northwest of the country.77
U.S. assistance also supports the reintegration of Cambodian deportees from the United States.78
(See textbox, “U.S. Deportations of Cambodians,” below.)
U.S. Deportations of Cambodians
Since 2002, when the two countries signed a Memorandum of Understanding on repatriation, over 1,000
Cambodian nationals who were permanent U.S. residents and who had been convicted of felony crimes were
deported to Cambodia.79 Many of them came to the United States during the 1980s as refugee children, and some
had never lived in Cambodia. Many Cambodians subject to deportation have jobs and families in the United States,
and many served prison time in the United States for crimes committed during their youth, including minor
offenses.80 Since 2017, the Department of Homeland Security’s Immigration and Customs Enforcement agency
(ICE) has deemed that the Cambodian government was uncooperative or hindering U.S. deportation efforts, and
in violation of its international obligations, and placed Cambodia on a list of “recalcitrant countries.” The U.S.
government then has imposed limited visa restrictions upon Cambodian Foreign Ministry employees and their
families pursuant to Section 243(d) of the Immigration and Nationality Act.81
Cambodia and China
Observers have called Cambodia the Southeast Asian country upon which China exerts the
greatest influence, and China’s “most reliable partner in Southeast Asia.”82 According to some
sources, China, whose assistance is not included in OECD data, is the largest provider of
development aid to the kingdom largely through billions of dollars in infrastructure projects.83
Some experts argue that China’s economic engagement has helped reduce U.S. and Western
influence in Cambodia.84 Hun Sen’s condemnation of Russia’s invasion of Ukraine, however,
contrasted with China’s position of neutrality, and Cambodia has voted for two U.N. resolutions
in support of Ukraine, while China abstained.85

76 Landmine and Cluster Munition Monitor, “Cambodia,” updated November 16, 2021.
77 The Halo Trust, “Cambodia,” at https://www.halotrust.org/where-we-work/south-asia/cambodia/.
78 Department of State, Congressional Budget Justification, Foreign Operations, Appendix 2, FY2023; The
Consolidated Appropriations Act, FY2023 (P.L. 117-328) USAID, “Cambodia: Country Profile,” 2022.
79 Vivian Ho, “‘Like Becoming a Refugee Again’: They Paid for Their Crimes. The US Deported Them Anyway,” The
Guardian, August 18, 2023.
80 Asian Law Caucus, “Resources for Southeast Asian Refugees Facing Deportation,” November 10, 2022.
81 U.S. Immigration and Customs Enforcement, “Visa Sanctions Against Multiple Countries Pursuant to Section 243(d)
of the Immigration and Nationality Act,” August 17, 2022. For further information, see CRS In Focus IF11025,
Immigration: “Recalcitrant” Countries and the Use of Visa Sanctions to Encourage Cooperation with Alien Removals,
by Jill H. Wilson.
82 Philip Heijmans, “China-Backed Dara Sakor Project in Cambodia Rings Alarm Bells in Washington,” Bloomberg,
July 7, 2019.
83 China is not a member of the OECD, and PRC economic assistance often does not meet OECD standards for ODA,
due to its large non-concessional loan component, commercial elements, and economic benefits accruing to China.
Heimkhemra Suy, “No Simple Solution to China’s Dominance in Cambodia,” East Asia Forum, December 26, 2020;
“What China’s Belt and Road Initiative Means for Cambodia,” USC US-China Institute, July 21, 2020.
84 Prak Chan Thul and Matthew Tostevin, “China’s Big Money Trumps U.S. Influence in Cambodia,” Reuters,
September11, 2017.
85 Shannon Tiezzi, “How Did Asian Countries Vote on the UN’s Ukraine Resolution:” The Diplomat, March 3, 2022;
United Nations, “Ukraine: General Assembly Passes Resolution Demanding Aid Access, by Large Majority,” UN
(continued...)
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Economic Engagement
Cambodia’s exports to China, its largest trading partner, totaled $1.8 billion in 2022. Its imports
from China, which include fabric for the country’s garment industry, totaled $14.1 billion.86
Cambodia and China signed a free trade agreement in 2020, which took effect in 2022. China is
the top foreign investor in Cambodia (roughly half of all foreign investment in 2021); other major
investors include Japan, Singapore, South Korea, and Vietnam.87 China is also a major provider of
financing, holding 42.7% of the kingdom’s foreign debt in 2021.88
PRC-backed infrastructure and hydropower projects have brought some developmental benefits
while also creating environmental problems, contributing to corruption and crime, and causing
disruptions and dislocation among some local communities, according to some observers.89 PRC
investment has been particularly concentrated in the city of Sihanoukville and elsewhere along
the Gulf of Thailand, with development projects including the construction of tourist and
gambling resorts, industrial zones, an international airport at Dara Sakor, and a deep-water
seaport in Kampot province. U.S. analysts express concern that the airport and seaport could be
used for military as well as civilian purposes.90 PRC investors reportedly have left over 1,000
unfinished and abandoned buildings in Sihanoukville following the halt of construction during the
COVID-19 pandemic.91
Military Relations
During the past decade, PRC military assistance to the Royal Cambodian Armed Forces has
included military trucks and helicopters, armored personnel carriers, light weapons such as anti-
aircraft guns, and financing.92 China also has provided military education, training, and technical
assistance.93 Since 2016, the two countries have carried out five Golden Dragon joint military
exercises. In March 2023, a reported 257 PRC and 583 Cambodian troops participated in joint
drills including naval and humanitarian exercises.94

News, March 24, 2022; Torn Chanritheara, “Cambodia Stands against Russian Annexation of Ukraine’s Regions,”
Cambodianess, October 1, 2022; “Cambodia PM Condemns Russian Invasion of Ukraine,” Reuters, March 28, 2022.
86 Trade Data Monitor.
87 Open Development, “Cambodia: Foreign Investors,” March 2023; “Chinese Investment in Cambodia Rises in 2021
despite Pandemic,” Xinhua, March 4, 2022.
88 Economist Intelligence Unit, “Country Report: Cambodia,” July 10, 2023.
89 Matthias Alfram, “Sihanoukville Pays the Price for Heavy Reliance on Chinese,” Bangkok Post, May 9, 2022; Brian
Eyler, “How China Turned Off the Tap on the Mekong,” Stimson Center, April 13, 2020; Kimkong Heng, “Chinese
Investment Strains Cambodian Society,” Nikkei Asia, July 22, 2019; Prak Chan Thul, “Chinese Investment in
Cambodian Province Pushes Up Crime Rate, Says Governor,” Reuters, January 26, 2018.
90 Hannah Beech, “A Jungle Airstrip Stirs Suspicions about China’s Plans for Cambodia,” International New York
Times, December 26, 2019. Jeremy Page, Gordon Lubold and Rob Taylor, “Naval Outpost in Cambodia Bolsters
China’s Ambitions,” Dow Jones Institutional News, July 22, 2019.
91 “’Ghost Buildings’ Show Boom Times Are Over for Cambodian Resort Town,” Radio Free Asia, August 16, 2022.
92 “Cambodian Army Purchased 290 Military Trucks from China,” Global Defence Mart, June 24, 2020; Keegan
Elmer, “China Pledges More Military Aid as Cambodia Prepares for Controversial Election,” South China Morning
Post, June 19, 2018; Prashanth Parameswaran, “A New Military Aid Boost for China-Cambodia Defense Ties?” The
Diplomat, February 1, 2018; “China Supplies Cambodia with Anti-Aircraft Hardware in New Military Aid,” Reuters,
November 6, 2015.
93 “China-Cambodia Military Relations Reach New High: Defense Spokesperson,” China Military Online, July 29,
2021; Prashanth Parameswaran, “China Just Gave Cambodia’s Military a Boost,” The Diplomat, May 27, 2015;
Aubrey Belford, “Chinese Influence in Cambodia Grows with Army School, Aid,” Reuters, April 2, 2015.
94 “China, Cambodia Kick Off Golden Dragon 2023 Joint Drills,” Radio Free Asia, March 23, 2023.
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Ream Naval Base
Since 2018, U.S. concerns have grown regarding PRC construction activities at Ream Naval
Base.95 Cambodian officials have stated the upgrades, including a new pier, support Cambodian
military modernization.96 Some experts say China may aim to use Ream to berth PRC military
supply ships and accommodate visiting PRC warships, enabling China to project power further
from the Chinese mainland.97 Cambodian officials have emphasized that hosting a foreign
military facility would be unconstitutional, although the government may provide access to
multiple countries.98 PRC officials reportedly have confirmed that “a portion of the base” would
be used by the Chinese military, although they denied that Cambodia has given China exclusive
rights to Ream.99

95 Andrew Salerno-Garthwaite, “China’s Secret Naval Base in Cambodia, Through Satellite Imagery,” Naval
Technology, March 14, 2023; “Construction at Cambodia’s Ream Picks Up Pace,” Asian Maritime Transparency
Initiative,” October 18, 2022; Niharika Mandhana and Chun Han Wong, “China to Upgrade Ream Naval Base in
Cambodia, Fueling U.S. Concerns,” Wall Street Journal, June 8, 2022.
96 Minnie Chan, “China’s Cambodian Navy Base Project Makes US Wary, But Fears It Will Host Aircraft Carrier are
Unfounded, Analysts Say,” South China Morning Post, July 27, 2023.
97 Rebecca Ratcliffe, “‘Ironclad Brothers’: What China Wants from Its Role in Cambodia’s Biggest Naval Base,” The
Guardian, June 9, 2022; Prashanth Parameswaran, “Why a New China Naval Outpost in Cambodia Would Matter,”
The Diplomat, July 23, 2019; Jeremy Page, Gordon Lubold and Rob Taylor, “Naval Outpost in Cambodia Bolsters
China’s Ambitions,” Wall Street Journal, July 22, 2019; Charles Dell, “Hiding in Plain Sight: Chinese Expansion in
Southeast Asia,” War on the Rocks, May 9, 2019.
98 “Cambodia and China Deny Naval Base Scheme as Australian PM Voices Concern,” Agence France Presse, June 8,
2022; Ankit Panda, “Cambodia’s Hun Sen Denies Chinese Naval Base Again—But What’s Really Happening?” The
Diplomat, June 2, 2020.
99 Ellen Nakashima and Cate Cadell, “China Secretly Building Naval Facility in Cambodia, Western Officials Say,”
Washington Post, June 6, 2022.
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Cambodia: Background and U.S. Relations

Khmer Rouge Tribunal
The Extraordinary Chambers in the Courts of Cambodia (ECCC, also known as the Khmer Rouge Tribunal), an
international court established through an agreement between the government of Cambodia and the United
Nations, began proceedings in 2006 to try Khmer Rouge leaders and officials responsible for grave violations of
national and international law.100 The ECCC has been financed through contributions by the Cambodian
government along with donations by foreign countries, particularly Japan, both directly to the ECCC and to a
U.N.-administered international trust fund. Between 2008 and 2017, the United States provided annual
contributions to the international trust fund. In addition, between 2005 and 2017, USAID provided a total of $9.8
mil ion to the Documentation Center of Cambodia, an archive, library, and public service center focused upon
Khmer Rouge atrocities.101
ECCC prosecutors charged five former Khmer Rouge leaders with crimes against humanity and war crimes. In
2012, “chief executioner” Kaing Guek Eav, who ran the infamous Toul Sleng prison in Phnom Penh, was sentenced
to life in prison. Former Foreign Minister Ieng Sary died in March 2013, before the completion of his trial, while his
wife, former Minister of Social Affairs Ieng Thirith, was declared mentally unfit for trial. In August 2014, the court
sentenced former leaders Nuon Chea and Khieu Samphan each to life in prison for crimes against humanity, and in
a separate trial in November 2018, each was convicted of additional crimes, including genocide.102 Although
Cambodian and international human rights groups and the ECCC’s international judges advocated prosecuting
former mid-ranking Khmer Rouge officials, Hun Sen opposed further indictments, arguing that they would
undermine national stability.103 In 2022, the Cambodian National Assembly voted to bring the ECCC to a close,
and in September 2022, the court made its final ruling, rejecting an appeal by Khieu Samphan, age 91.104
Hydropower Projects
Domestic and regional demand for energy and foreign investment, largely from China, have
driven hydropower projects in Cambodia and neighboring countries. PRC firms reportedly have
invested over $2 billion in the construction of seven major dams in Cambodia.105 According to
some experts, dams on the upper Mekong River in China and unregulated, Chinese-built dams on
the Lower Mekong in Laos and Cambodia have caused erratic changes in water levels,
environmental degradation and ecological damage, loss of fish stocks, displacement of
communities, and adverse effects on livelihoods in Laos, Cambodia, and Vietnam.106 Cambodia
relies heavily on the Mekong and Tonle Sap Lake, which the river feeds into, for its food

100 The tribunal has 17 Cambodian judges and prosecutors and 10 international judges and prosecutors. As a safeguard
against bias, verdicts require a “super-majority”—a simple majority plus the vote of at least one international judge.
101 “United States Announces New Contribution to Help Preserve Cambodia’s Historical Documents,” USAID, April 3,
2017.
102 Sopheng Cheang, “Cambodia Says Khmer Rouge Tribunal That Convicted 3 Is Done,” Miami Herald, November
18, 2018.
103 Andrew Nachemson, “Last Khmer Rouge Cases Are in Limbo; Cambodian Judges on an International Tribunal
Block a Trial, Los Angeles Times, April 9, 2020; International Justice Monitor, “Khmer Rouge Tribunal Leaves
Unresolved Whether New Case Will Proceed to Trial,” January 9, 2020. “Expanding Khmer Rouge Trials Could Spark
War: Hun Sen,” The Nation, February 28, 2015.
104 Seth Mydans, “16 Years, 3 Convictions: The Khmer Rouge Trials Come to an End,” New York Times, September
22, 2022; Lindsey Kennedy and Nathan Southern, “Khmer Rouge Tribunal, Helping Cambodians Heal, Nears End,” Al
Jazeera, April 28, 2022; “Cambodia’s War Crimes Tribunal to Close by End of 2022,” Gulf Today, April 28, 2022.
105 “Chinese Investment in Energy Creates New History for Cambodia: Cambodian Minister,” China Daily, October
11, 2016.
106 Brian Eyler, “How China Turned Off the Tap on the Mekong River,” Stimson Center, April 13, 2020, updated May
8, 2021, at https://www.stimson.org/2020/new-evidence-how-china-turned-off-the-mekong-tap/; Hannah Beech, “‘Our
River Was Like a God’: How Dams and China’s Might Imperil the Mekong,” New York Times, October 12, 2019;
Nyshka Chandran, “Southeast Asia Is Betting on Hydropower, But There Are Risks of Economic Damage,” CNBC,
August 9, 2018.
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Cambodia: Background and U.S. Relations

security.107 In 2019, a number of issues, including drought and damming of the Mekong, resulted
in record-breaking low levels of water, which compounded depleted fisheries and worsening soil
conditions.108 In March 2020, the Cambodian government announced that hydropower projects
along the Mekong would be put on hold for 10 years and that it would pursue alternative sources
of energy.109

Author Information

Thomas Lum

Specialist in Asian Affairs

Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
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copy or otherwise use copyrighted material.

107 Zoe Osbourne, “Mekong Basin’s Vanishing Fish Signal Tough Times Ahead in Cambodia,” The Guardian,
December 16, 2019.
108 Andrew Nachemson, “Cambodia’s Lifeline Threatened as Mekong Recedes to Historic Low,” Al Jazeera,
September 23, 2019.
109 Prak Chan Thul, “Cambodia Puts Plans for Mainstream Mekong Dams on Hold For 10 Years, Official Says,”
Reuters, March 10, 2020; Tyler Roney, “Mekong Dams Destroy Tonle Sap Lake,” thethirdpole.net, April 27, 2020;
“Southeast Asia’s Hydropower Boom Grinds to a Halt as COVID-19 Stalls Projects,” Channel NewsAsia, April 21,
2020.
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