Prelude to the Russian invasion of Ukraine in the context of "Normandy Format"

On 24 February 2022, Russia invaded Ukraine, starting the largest and deadliest war in Europe since World War II. It is a major escalation of the war between the two countries that began in 2014. The fighting has caused hundreds of thousands of military casualties and tens of thousands of Ukrainian civilian casualties. As of 2025, Russian troops occupy about 20% of Ukraine. From a population of 41 million, about 8 million Ukrainians had been internally displaced and more than 8.2 million had fled the country by April 2023, 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 that it was to support the Russian-backed breakaway republics of Donetsk and Luhansk, whose paramilitary forces had been fighting Ukraine in the war in Donbas since 2014. Putin espoused irredentist and imperialist views challenging Ukraine's legitimacy as a state, baselessly claimed that the Ukrainian government were neo-Nazis committing genocide against the Russian minority in the Donbas, and said 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.

On 17 December 2021, during the prelude to the Russian invasion of Ukraine, Russia published a list of demands to the West for security guarantees in the form of two draft treaties with the North Atlantic Treaty Organization (NATO) and the United States. The proposals included a ban on Ukraine and other ex-Soviet countries from joining NATO, and a roll-back in deployments of NATO troops and weapons in Central and Eastern Europe. Russia had long been concerned with the decline in its self-regarded sphere of influence in the former Soviet republics, which were aligning themselves with the West economically and politically, and had been dissatisfied with the existing security architecture and NATO expansion. The demands, issued during a period of high tensions during which about 100,000 Russian troops were massed on Ukraine's borders, were widely seen as an ultimatum and attempt by Russia to exert pressure and influence on Western countries. The main demands were rejected by NATO and the United States on 26 January 2022; the Russian invasion of Ukraine followed less than a month later on 24 February.

"Address concerning the events in Ukraine" (Russian: Обращение по поводу событий на Украине, romanized: Obrashcheniye po povodu sobyty na Ukraine) was a televised address by Russian president Vladimir Putin, broadcast on 21 February 2022, announcing that the Russian government would recognise the Ukrainian separatist regions of the Donetsk People's Republic and the Luhansk People's Republic as independent. During the speech, Putin also made a number of claims regarding Ukrainian history and Ukrainian domestic politics. Genocide experts, historians and other experts have shown these claims to be false and possibly justifying a genocide. The speech, which marked a significant escalation in the culminating Russo-Ukrainian crisis, was followed three days later by another speech declaring "a special military operation" in Ukraine—announcing the Russian invasion of Ukraine,which began minutes later.