Secretary of State John Kerry has said the United States and Russia agree on "some fundamental principles" for Syria.
Kerry spoke in an MSNBC interview on September 29, after Presidents Barack Obama and Vladimir Putin met on the sidelines of the UN General Assembly.
He said there was agreement that the extremist Islamic State (IS) group "needs to be taken on" and that "there needs to be a managed [political] transition" in Syria.
But he said Moscow, a leading backer of the Damascus regime, must understand that there can be no peace in Syria without removing President Bashar al-Assad.
The United States has previously criticized the Kremlin for bolstering Assad with advanced weaponry, aircraft, and military personnel.
Kerry also said he plans to meet again with his Russian counterpart, Sergei Lavrov, on September 30.
Lavrov earlier described the talks between Putin and Obama as "very constructive," saying they touched upon "the possibilities for the United States and Russia to cooperate closely" on Syria.
Speaking to the RT television channel after Putin and Obama's first one-on-one meeting in meeting in two years, Lavrov said the two leaders "agreed that our common goal is to defeat" the IS militants.
"Both Russia and the United States are absolutely determined not to allow them to succeed," Lavrov added.