The United States is looking into the option of sending lethal defensive weapons to war-torn Ukraine "if diplomacy fails".

U.S. President Barack Obama announced this after talks in Washington with German Chancellor Angela Merkel on February 9, aimed to end the crisis in eastern Ukraine, where pro-Russian rebels are fighting government troops

Obama said he hoped that a diplomatic solution was still possible, but that was clear Russia had violated its commitments on Ukraine.

Merkel traveled to Washington February 9 to discuss with Obama the French-German efforts to revive last year's Minsk peace agreement, which collapsed amid intensified fighting in eastern Ukraine.

"It's clear that they violated just about every commitment they made in the Minsk agreement, instead of withdrawing from eastern Ukraine, Russian forces continued to operate there, training separatists and helping to coordinate attacks, instead of withdrawing its arms Russia has sent in more tanks and armored personnel carriers and heavy artillery," said Obama, according to RFE/RL.

Merkel, who has repeately made clear she opposed supplying Kyiv with lethal arms, admitted diplomatic efforts were largely unsuccessful, but said that they would continue. 

"I've always said that I don't see a military solution to this conflict but we have to put all our efforts into bringing about a diplomatic solution," Merkel said.