Civil war in Syria enters its third year this month. What started as protests against Syrian President Bashar Assad during the Arab Spring has turned into a military campaign that's left more than 70,000 people dead and another 1 million displaced.
Russian Foreign Minister Sergei Lavrov said last week that, despite the bloodshed, his government wasn't joining the calls for regime change in Damascus.
State Department spokeswoman Victoria Nuland said there's no place for Assad in post-war Syria. She added that Washington was looking to Moscow to use its influence in Syria but noted talking points varied significantly.
"It is no secret that we still don't see eye-to-eye on all aspects of Syria, including the fact that the Russians continue to supply arms and other things to the Syrian regime," she said.
Syria counts Russia as its top weapons supplier. Moscow says any military sales are conducted under contracts made before the war.
Efforts to pass a resolution against Syria at the U.N. Security Council have been met with opposition from permanent member Russia, which said draft resolutions lacked balance.