The White House says there is "no evidence" that Russia has withdrawn troops from its border with Ukraine.
The comments from White House spokesman Josh Earnest came shortly after Russian President Vladimir Putin said his country had pulled troops back from the border. Earnest says the White House would welcome a "meaningful and transparent" withdrawal if it were to take place.
Putin also urged insurgents in southeastern Ukraine to postpone their planned referendum Sunday on autonomy. Earnest said the US believes the referendum should be cancelled, not postponed.
Russia has had about 40,000 troops positioned on Ukraine's border for several weeks. The US says those forces are there to stir up instability in Ukraine, not for regular training exercises.
