The Obama Administration maintains President Bashar Assad shouldn't lead Syria any longer, rejecting a Russian claim that the US has changed its position.
Interfax news agency quoted Russian Deputy Foreign Minister Sergei Ryabkov saying Washington now accepts Moscow's argument that Assad's future shouldn't be open for negotiation right now.
Assad's Russian-backed government and Western-supported rebels recently concluded peace talks and will meet again next month.
State Department spokesman John Kirby said: "Any suggestion that we have changed in any way our view of Assad's future is false. Assad has lost his legitimacy to govern. We haven't changed our view on that."
America softened demands last year for Assad's immediate departure, but still insists he should resign at some point in a political transition process. Russia says outside powers shouldn't try to determine Syria's leadership. Assad has not indicated he will leave power.
At least 250,000 people - and perhaps as many as a half million - have been killed in the five-year civil war, which has spawned Europe's worst refugee crisis since World War II and has led to the emergence of Isis.