MICHAEL KIMMAGE is Professor of History at the Catholic University of America. He is the author of Collisions: The Origins of the War in Ukraine and the New Global Instability.

Explosions rocked Kyiv and multiple other regions in the early hours of July 16, with Ukraine's Air Force issuing repeated warnings of drone and missile strikes across the country, including western o

Vladimir Putin’s conduct has prompted Donald Trump’s shift as Russia’s war effort in Ukraine has gotten only more aggressive.

It remains to be seen just how lasting and severe President Donald Trump’s turn against Vladimir Putin will be. Trump has criticized the Russian president in unprecedented terms in recent days and signaled he’ll send vital weapons to Ukraine.

U.S. President Donald Trump said he was disappointed but not done with Russian President Vladimir Putin, according to a BBC interview published on Tuesday, hours after Trump announced new weapons for Ukraine and threatened Russia with sanctions.

Donald Trump tells the BBC he is "disappointed" with Vladimir Putin over the lack of a ceasefire deal in Ukraine.

President Trump warned Ukraine not to strike Moscow with the military aid that the U.S. will begin sending soon. All of it is sparking sharp reactions inside Russia. NBC News’ Keir Simmons reports.