Attacks on Russian military bases in south Ukraine increasing, Ukrainian officials say

Armed conflict in eastern Ukraine erupted in early 2014 following Russia’s annexation of Crimea. The previous year, protests in Ukraine’s capital, Kyiv, against Ukrainian President Viktor Yanukovych’s decision to reject a deal for greater economic integration with the European Union (EU) were met with a violent crackdown by state security forces. The protests widened, escalating the conflict, and President Yanukovych fled the country in February 2014.

One month later, in March 2014, Russian troops took control of the Ukrainian region of Crimea. Russian President Vladimir Putin cited the need to protect the rights of Russian citizens and Russian speakers in Crimea and southeast Ukraine. Russia then formally annexed the peninsula after Crimeans voted to join the Russian Federation in a disputed local referendum. The crisis heightened ethnic divisions, and two months later, pro-Russian separatists in the eastern Ukrainian regions of Donetsk and Luhansk held their own independence referendums.

Armed conflict in eastern Ukraine erupted in early 2014 following Russia’s annexation of Crimea. The previous year, protests in Ukraine’s capital, Kyiv, against Ukrainian President Viktor Yanukovych’s decision to reject a deal for greater economic integration with the European Union (EU) were met with a violent crackdown by state security forces. The protests widened, escalating the conflict, and President Yanukovych fled the country in February 2014.

One month later, in March 2014, Russian troops took control of the Ukrainian region of Crimea. Russian President Vladimir Putin cited the need to protect the rights of Russian citizens and Russian speakers in Crimea and southeast Ukraine. Russia then formally annexed the peninsula after Crimeans voted to join the Russian Federation in a disputed local referendum. The crisis heightened ethnic divisions, and two months later, pro-Russian separatists in the eastern Ukrainian regions of Donetsk and Luhansk held their own independence referendums.

Armed conflict in the regions quickly broke out between Russian-backed forces and the Ukrainian military. Russia denied military involvement, but both Ukraine and the North Atlantic Treaty Organization (NATO) reported the buildup of Russian troops and military equipment near Donetsk and Russian cross-border shelling immediately following Crimea’s annexation. The conflict transitioned to an active stalemate, with regular shelling and skirmishes occurring along frontlines separating Russian- and Ukrainian-controlled eastern border regions.

Beginning in February 2015, France, Germany, Russia, and Ukraine attempted to kickstart negotiations to bring an end to the violence through the Minsk Accords. The agreement framework included provisions for a ceasefire, withdrawal of heavy weaponry, and full Ukrainian government control throughout the conflict zone. Efforts to reach a diplomatic settlement and satisfactory resolution, however, were largely unsuccessful.

In April 2016, NATO announced the deployment of four battalions to Eastern Europe, rotating troops through Estonia, Latvia, Lithuania, and Poland to deter possible future Russian aggression elsewhere on the continent, particularly in the Baltics. In September 2017, the United States also deployed two U.S. Army tank brigades to Poland to further bolster NATO’s presence in the region.

In January 2018, the United States imposed new sanctions on twenty-one individuals–including a number of Russian officials–and nine companies linked to the conflict in eastern Ukraine. In March 2018, the U.S. Department of State approved the sale of anti-tank weapons to Ukraine, the first sale of lethal weaponry since the conflict began. In October 2018, Ukraine joined the United States and seven other NATO countries in a series of large-scale air exercises in western Ukraine. The exercises came after Russia held its own annual military exercises in September 2018, the largest since the fall of the Soviet Union.

In October 2021, months of intelligence gathering and observations of Russian troop movements, force build-up, and military contingency financing culminated in a White House briefing with U.S. intelligence, military, and diplomatic leaders on a near-certain mass-scale Russian invasion of Ukraine. The only remaining questions were when the attack would take place and whether the United States would be able to convince allies to act preemptively. Both were answered on February 24, 2022, when Russian forces invaded a largely unprepared Ukraine after Russian President Vladimir Putin authorized a “special military operation” against the country. In his statement, Putin claimed that the goal of the operation was to demilitarize and denazify Ukraine and end the alleged genocide of Russians in Ukrainian territory.

In the days and weeks leading up to the invasion, the Joe Biden administration made the unconventional decision to reduce information-sharing constraints and allow for the broader dissemination of intelligence and findings, both with allies—including Ukraine—and publicly. The goal of this strategy was to bolster allied defenses and dissuade Russia from taking aggressive action. Commercial satellite imagery, social media posts, and published intelligence from November and December 2021 showed armor, missiles, and other heavy weaponry moving toward Ukraine with no official explanation from the Kremlin. By the end of 2021, more than one hundred thousand Russian troops were in place near the Russia-Ukraine border, with U.S. intelligence officials warning of a Russian invasion in early 2022. In mid-December 2021, Russia’s foreign ministry called on the United States and NATO to cease military activity in Eastern Europe and Central Asia, commit to no further NATO expansion toward Russia, and prevent Ukraine from joining NATO in the future. The United States and other NATO allies rejected these demands and threatened to impose severe economic sanctions if Russia took aggressive action against Ukraine.

In early February 2022, satellite imagery showed the largest deployment of Russian troops to its border with Belarus since the end of the Cold War. Negotiations between the United States, Russia, and European powers—including France and Germany—failed to bring about a resolution. In late February 2022, the United States warned that Russia intended to invade Ukraine, citing Russia’s growing military presence at the Russia-Ukraine border. President Putin then ordered troops to Luhansk and Donetsk, claiming the troops served a “peacekeeping” function. The United States responded by imposing sanctions on the regions and the Nord Stream 2 gas pipeline a few days later. Nevertheless, just prior to the invasion, U.S. and Ukrainian leaders remained at odds regarding the nature and likelihood of an armed Russian threat, with Ukrainian officials playing down the possibility of an incursion and delaying the mobilization of their troops and reserve forces.

On February 24, 2022, during a last-ditch UN Security Council effort to dissuade Russia from attacking Ukraine, Putin announced the beginning of a full-scale land, sea, and air invasion of Ukraine targeting Ukrainian military assets and cities across the country. U.S. President Joe Biden declared the attack “unprovoked and unjustified” and issued severe sanctions against top Kremlin officials, including Putin and Russian Foreign Minister Sergey Lavrov; four of Russia’s largest banks; and the Russian oil and gas industry in coordination with European allies. On March 2, 141 of 193 UN member states voted to condemn Russia’s invasion in an emergency UN General Assembly session, demanding that Russia immediately withdraw from Ukraine.

Since the 2014 annexation of Crimea, Ukraine has also increasingly been the target of thousands of cyberattacks. In December 2015, more than 225,000 people lost power across Ukraine in an attack on electricity generation firms, and, in December 2016, parts of Kyiv experienced another power blackout following a similar attack targeting a Ukrainian utility company. In June 2017, government and business computer systems in Ukraine were hit by the NotPetya cyberattack, which has been attributed to Russia; the attack spread to computer systems worldwide and caused billions of dollars in damages. In February 2022, Ukrainian government websites, including the defense and interior ministries, banking sites, and other affiliated organizations were targeted by distributed denial-of-service attacks alongside the Russian invasion.