Russia’s Invasion of Ukraine: NATO Response
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INSIGHTi
Russia’s Invasion of Ukraine:
NATO Response
Updated March 21, 2022
The 30-member North Atlantic Treaty Organization (NATO; see Figure 1) has condemned Russia’s
February 2022 invasion of Ukraine, which it has characterized as the “most dangerous moment in
European security in a generation.” Underscoring its role as a defensive alliance, NATO has joined the
United States in declaring that it would not deploy forces to Ukraine, which is not a NATO member.
NATO has, however, significantly enhanced its defensive force posture in the eastern part of the alliance
and reiterated its solidarity with Ukraine.
NATO officials also have expressed support for substantial bilateral assistance, including arms transfers,
provided to Ukraine by NATO members since the invasion. According to some reports, as of early March,
arms transfers from NATO allies to Ukraine had included more than 17,000 anti-tank missiles and 2,000
Stinger anti-aircraft missiles.
Enhanced Deterrence
Since Russia’s first invasion of Ukraine in 2014, NATO has renewed its focus on territorial defense and
deterring Russian aggression, including through an Enhanced Forward Presence (EFP) of four
multinational battle groups stationed in the Baltic states (Estonia, Latvia, and Lithuania) and Poland. The
battle groups, which have more than doubled in size since early February—from about 5,000 troops to
16,400 in mid-March—are led by the United Kingdom (Estonia), Canada (Latvia), Germany (Lithuania),
and the United States (Poland). NATO also has established a Multinational Division Southeast
headquartered in Romania to coordinate a Tailored Forward Presence (TFP) in the Black Sea region.
According to NATO, 40,000 allied troops are now under direct NATO command in the eastern part of the
alliance, along with more than 130 allied fighter jets on high alert and more than 200 allied ships at sea in
the region. In addition to U.S. deployments (see below), new NATO deployments include more than
1,000 soldiers from the UK to Estonia and Poland; 800 French and Belgian troops to Romania; 350
additional German troops to Lithuania and a German-Dutch Patriot air defense system as part of a new
NATO battlegroup in Slovakia; and additional fighter jets, ships, and troops from numerous allies.
On February 24, NATO announced that the alliance had activated defense plans that would allow military
commanders to deploy elements of the NATO Response Force (NRF), a multinational rapid-reaction force
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of 40,000 personnel with land, air, maritime, and special operations components. In January 2022, the
Biden Administration announced that 8,500 U.S. soldiers would be placed on high readiness for possible
deployment to the NRF.
Despite these measures, NATO members remain concerned about the potential for a wider conflict. Even
prior to Russia’s invasion, some studies of NATO’s force posture concluded that NATO forces would
struggle to defend NATO’s most vulnerable allies—for example, the Baltic states—from a Russian attack.
Ahead of NATO’s June 2022 summit in Madrid, Spain, NATO leaders are expected to consider more
substantive enhancements to NATO’s force posture, including permanently stationing troops in Eastern
Europe. Until now, NATO’s military presence in the region has been portrayed as rotational, reflecting
some allies’ reluctance to endorse a permanent presence that could be perceived as provoking Russia.
U.S. Deterrence Deployments
Following Russia’s 2014 occupation of Crimea, the Obama Administration increased the U.S. military
presence in Europe under the European Reassurance Initiative, later renamed the European Deterrence
Initiative (EDI). The cornerstone of EDI has been Operation Atlantic Resolve, the rotational deployment
of approximately 7,000 U.S. armed forces in Europe, including an Armored Brigade Combat Team (BCT)
in Central and Eastern Europe. According to the Department of Defense, an additional 15,000 U.S.
soldiers have deployed to Europe since early February 2022 to augment defense and deterrence efforts,
bringing the total U.S. force posture in Europe, including permanently stationed forces, to approximately
100,000 military personnel. The new deployments bring the total U.S. military presence in Poland to
about 9,500—including 800 soldiers deployed to the U.S.-led NATO battlegroup—and in Romania to
about 1,900. In addition, about 800 U.S. soldiers and 20 attack helicopters have been deployed to the
Baltic region, along with eight F-35 joint strike fighters deployed to NATO’s eastern flank. An additional
7,000 U.S. soldiers, including a BCT, have deployed to Germany to reinforce deterrence efforts, including
as part of the NRF.
Considerations for Congress
Many Members of Congress have condemned Russia’s invasion of Ukraine and are considering numerous
policy responses, including with respect to NATO’s role. Key considerations include the following:
NATO and U.S. Force Posture in Europe. Russia’s invasion has heightened concerns
about NATO’s capacity to defend NATO member states, particularly the Baltic states,
from a possible Russian military attack. Key factors to consider could include NATO
member states’ willingness and capacity to respond to an intentional or inadvertent attack
on NATO member states, and what form that response may take; the U.S. role in
responding to a possible attack; sustaining alliance cohesion regarding the appropriate
response to a potential attack; and the appropriate U.S. and NATO force posture in the
region.
Future of NATO-Russia Relations. NATO’s current Strategic Concept, adopted in
2010, outlines a desire for “strategic partnership” with Russia. As the alliance prepares to
adopt a new Strategic Concept in June 2022, U.S. policymakers could advocate
fundamental changes to NATO’s approach to Russia, including a more robust allied force
posture in Eastern Europe. Policymakers may also reassess NATO’s prior willingness to
negotiate with Russia on European security arrangements, including arms control and
NATO’s nuclear force posture.
NATO’s Role in Supporting Ukraine. With support from Congress, NATO has
consistently rejected Russian demands for a halt to NATO’s “open door” enlargement
policy. Russia’s invasion of a NATO aspirant that borders four NATO members could
Congressional Research Service
3
raise questions about NATO’s obligations to Ukraine; NATO’s relations with other
aspirants, such as Georgia; and the future of NATO enlargement. With respect to Ukraine,
some Members of Congress have called for more direct support to counter Russia and
defend Ukraine. Others, including the Administration, remain cautious about options that
they believe could escalate the conflict.
Figure 1. NATO Europe
Source: Map created by CRS.
Notes: NATO members Canada and the United States are not depicted.
Author Information
Paul Belkin
Analyst in European 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 than public understanding of
information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role.
CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United
States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However,
Congressional Research Service
4
as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the
permission of the copyright holder if you wish to copy or otherwise use copyrighted material.
IN11866 · VERSION 3 · UPDATED
INSIGHTi
Russia’s Invasion of Ukraine:
NATO Response
Updated March 21, 2022
The 30-member North Atlantic Treaty Organization (NATO; see Figure 1) has condemned Russia’s
February 2022 invasion of Ukraine, which it has characterized as the “most dangerous moment in
European security in a generation.” Underscoring its role as a defensive alliance, NATO has joined the
United States in declaring that it would not deploy forces to Ukraine, which is not a NATO member.
NATO has, however, significantly enhanced its defensive force posture in the eastern part of the alliance
and reiterated its solidarity with Ukraine.
NATO officials also have expressed support for substantial bilateral assistance, including arms transfers,
provided to Ukraine by NATO members since the invasion. According to some reports, as of early March,
arms transfers from NATO allies to Ukraine had included more than 17,000 anti-tank missiles and 2,000
Stinger anti-aircraft missiles.
Enhanced Deterrence
Since Russia’s first invasion of Ukraine in 2014, NATO has renewed its focus on territorial defense and
deterring Russian aggression, including through an Enhanced Forward Presence (EFP) of four
multinational battle groups stationed in the Baltic states (Estonia, Latvia, and Lithuania) and Poland. The
battle groups, which have more than doubled in size since early February—from about 5,000 troops to
16,400 in mid-March—are led by the United Kingdom (Estonia), Canada (Latvia), Germany (Lithuania),
and the United States (Poland). NATO also has established a Multinational Division Southeast
headquartered in Romania to coordinate a Tailored Forward Presence (TFP) in the Black Sea region.
According to NATO, 40,000 allied troops are now under direct NATO command in the eastern part of the
alliance, along with more than 130 allied fighter jets on high alert and more than 200 allied ships at sea in
the region. In addition to U.S. deployments (see below), new NATO deployments include more than
1,000 soldiers from the UK to Estonia and Poland; 800 French and Belgian troops to Romania; 350
additional German troops to Lithuania and a German-Dutch Patriot air defense system as part of a new
NATO battlegroup in Slovakia; and additional fighter jets, ships, and troops from numerous allies.
On February 24, NATO announced that the alliance had activated defense plans that would allow military
commanders to deploy elements of the NATO Response Force (NRF), a multinational rapid-reaction force
Congressional Research Service
https://crsreports.congress.gov
IN11866
CRS INSIGHT
Prepared for Members and
Committees of Congress
Congressional Research Service
2
of 40,000 personnel with land, air, maritime, and special operations components. In January 2022, the
Biden Administration announced that 8,500 U.S. soldiers would be placed on high readiness for possible
deployment to the NRF.
Despite these measures, NATO members remain concerned about the potential for a wider conflict. Even
prior to Russia’s invasion, some studies of NATO’s force posture concluded that NATO forces would
struggle to defend NATO’s most vulnerable allies—for example, the Baltic states—from a Russian attack.
Ahead of NATO’s June 2022 summit in Madrid, Spain, NATO leaders are expected to consider more
substantive enhancements to NATO’s force posture, including permanently stationing troops in Eastern
Europe. Until now, NATO’s military presence in the region has been portrayed as rotational, reflecting
some allies’ reluctance to endorse a permanent presence that could be perceived as provoking Russia.
U.S. Deterrence Deployments
Following Russia’s 2014 occupation of Crimea, the Obama Administration increased the U.S. military
presence in Europe under the European Reassurance Initiative, later renamed the European Deterrence
Initiative (EDI). The cornerstone of EDI has been Operation Atlantic Resolve, the rotational deployment
of approximately 7,000 U.S. armed forces in Europe, including an Armored Brigade Combat Team (BCT)
in Central and Eastern Europe. According to the Department of Defense, an additional 15,000 U.S.
soldiers have deployed to Europe since early February 2022 to augment defense and deterrence efforts,
bringing the total U.S. force posture in Europe, including permanently stationed forces, to approximately
100,000 military personnel. The new deployments bring the total U.S. military presence in Poland to
about 9,500—including 800 soldiers deployed to the U.S.-led NATO battlegroup—and in Romania to
about 1,900. In addition, about 800 U.S. soldiers and 20 attack helicopters have been deployed to the
Baltic region, along with eight F-35 joint strike fighters deployed to NATO’s eastern flank. An additional
7,000 U.S. soldiers, including a BCT, have deployed to Germany to reinforce deterrence efforts, including
as part of the NRF.
Considerations for Congress
Many Members of Congress have condemned Russia’s invasion of Ukraine and are considering numerous
policy responses, including with respect to NATO’s role. Key considerations include the following:
NATO and U.S. Force Posture in Europe. Russia’s invasion has heightened concerns
about NATO’s capacity to defend NATO member states, particularly the Baltic states,
from a possible Russian military attack. Key factors to consider could include NATO
member states’ willingness and capacity to respond to an intentional or inadvertent attack
on NATO member states, and what form that response may take; the U.S. role in
responding to a possible attack; sustaining alliance cohesion regarding the appropriate
response to a potential attack; and the appropriate U.S. and NATO force posture in the
region.
Future of NATO-Russia Relations. NATO’s current Strategic Concept, adopted in
2010, outlines a desire for “strategic partnership” with Russia. As the alliance prepares to
adopt a new Strategic Concept in June 2022, U.S. policymakers could advocate
fundamental changes to NATO’s approach to Russia, including a more robust allied force
posture in Eastern Europe. Policymakers may also reassess NATO’s prior willingness to
negotiate with Russia on European security arrangements, including arms control and
NATO’s nuclear force posture.
NATO’s Role in Supporting Ukraine. With support from Congress, NATO has
consistently rejected Russian demands for a halt to NATO’s “open door” enlargement
policy. Russia’s invasion of a NATO aspirant that borders four NATO members could
Congressional Research Service
3
raise questions about NATO’s obligations to Ukraine; NATO’s relations with other
aspirants, such as Georgia; and the future of NATO enlargement. With respect to Ukraine,
some Members of Congress have called for more direct support to counter Russia and
defend Ukraine. Others, including the Administration, remain cautious about options that
they believe could escalate the conflict.
Figure 1. NATO Europe
Source: Map created by CRS.
Notes: NATO members Canada and the United States are not depicted.
Author Information
Paul Belkin
Analyst in European 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 than public understanding of
information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role.
CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United
States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However,
Congressional Research Service
4
as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the
permission of the copyright holder if you wish to copy or otherwise use copyrighted material.
IN11866 · VERSION 3 · UPDATED