Moscow’s illegal annexation of Crimea on March 18, 2014, was recognized only by countries such as North Korea and Sudan.

U.S. President Donald Trump told President Volodymyr Zelenskiy on Monday that the United States would help guarantee Ukraine's security in any deal to end Russia's war there, though the extent of any assistance was not immediately clear.

Russia’s illegal seizure of the Crimean Peninsula from Ukraine in March 2014 was quick and bloodless, and it sent Moscow’s relations with the West into a downward spiral unseen since the Cold War.

Russian leader Vladimir Putin agreed at his summit with President Donald Trump that the United States and its European allies could offer Ukraine a security guarantee resembling NATO’s collective defense mandate as part of an eventual deal to end the war,