It is quite possible that Monday's meeting in the White House could prove even more crucial to the future of Ukraine - and for all of Europe's security - than last Friday's US-Russia summit in Alaska. On the surface, that Putin-Trump reunion seemed to live down to every expectation.

First lady Melania Trump called on Russian President Vladimir Put to protect the innocence of children in a letter made public by U.S. President Donald Trump on Sunday.

Donald Trump's meeting with Russian president Vladmir Putin was either a "disaster" or a success, depending on whom you ask — and on Sunday NBC's Kristen Welker asked both Sen. Chris Murphy and Secretary of State Marco Rubio.

The Alaska summit between the U.S. and Russian leaders showcased their mutual animosity for the former president.

In a summit meeting marked by red carpets, handshakes and military flyovers, President Vladimir Putin made his first trip to the United States in a decade and was greeted warmly by President Donald Trump.

The highly anticipated summit ended without a breakthrough. Afterwards, Trump said Ukraine and Russia should proceed straight to seeking a full peace deal instead of a cease-fire.

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,