Russo-Ukrainian war (2022–present)

On 24 February 2022, Russia invaded Ukraine, starting the largest and deadliest war in Europe since World War II, in a major escalation of the existing war between the two countries that began when Russia attacked Ukraine in 2014. The fighting has caused hundreds of thousands of military casualties and tens of thousands of Ukrainian civilian casualties. As of May 2026, Russian troops occupy roughly 20% of Ukraine. From a population of 41 million, about 8 million Ukrainians have been internally displaced and 6–7 million have fled the country, creating Europe's largest refugee crisis since World War II. In late 2021, Russia massed troops near Ukraine's borders and issued demands to the West, including a ban on Ukraine ever joining NATO. After repeatedly denying having plans to attack Ukraine, on 24 February 2022, Russian president Vladimir Putin announced a "special military operation", saying it was to support the Russian-backed breakaway republics of Donetsk and Luhansk, whose paramilitary forces had been fighting Ukraine in the Donbas War since 2014. Putin espoused irredentist and imperialist views challenging Ukraine's legitimacy as a state. He claimed without evidence that the Ukrainian government were neo-Nazis committing genocide against the Russian minority in the Donbas, and that Russia's goal was to "demilitarise and denazify" Ukraine. Russian air strikes and a ground invasion were launched on a northern front from Belarus towards the capital Kyiv, a southern front from occupied Crimea, and an eastern front from the Donbas towards Kharkiv. Ukraine enacted martial law, ordered a general mobilisation, and severed diplomatic relations with Russia. Russian troops retreated from the north and the outskirts of Kyiv by April 2022, after encountering stiff resistance and logistical challenges. The Bucha massacre was uncovered after their withdrawal. Russia launched an offensive in the Donbas and captured Mariupol after a destructive siege. Russia continued to bomb military and civilian targets far from the front, and struck Ukraine's energy grid during winter months. In late 2022, Ukraine launched successful counteroffensives in the south and east, liberating most of Kharkiv Oblast. Soon after, Russia illegally annexed four partly-occupied provinces. In November, Ukraine liberated the city of Kherson and all land west of the Dnipro river. After small but steady Russian advances in the east in the first half of 2024, Ukraine launched a cross-border offensive into Russia's Kursk Oblast in August, where North Korean soldiers were sent to help Russia. The United Nations Human Rights Office reports that Russia is committing severe human rights violations in occupied Ukraine. Russia's attacks on civilians, as well as its policies in occupied territories, have led to allegations of genocide. The direct cost of the war for Russia has been estimated as over US$450 billion, while the World Bank Group estimates the cost of reconstruction in Ukraine at US$588 billion. The Russian invasion was met with international condemnation. Many countries imposed sanctions on Russia and its ally Belarus while providing humanitarian and military aid to Ukraine. Protests occurred around the world, with anti-war protesters in Russia being met by mass arrests and greater media censorship. War-related disruption to Ukrainian agriculture and shipping worsened the world food crisis; war-related environmental damage was described as ecocide. The International Criminal Court (ICC) opened an investigation into crimes against humanity, war crimes, abduction of Ukrainian children, and genocide against Ukrainians. The ICC issued arrest warrants for Putin and five other Russian officials. Peace negotiations have stalled, and Russia has repeatedly refused calls for a ceasefire.