The Pentagon says Russian Defense Minister Sergei Shoygu has assured Defense Secretary Chuck Hagel that Russian forces will not invade Ukraine.
The two spoke by telephone Monday, with Hagel wanting clarification on Russia's intentions.
A Pentagon spokesman said Hagel emphasized how dangerous the situation is, and that Ukraine has the right to preserve law and order inside its borders. He reminded Shoygu that Russia faces more isolation if its aggression continues.
Hagel also asked for Russian help in freeing seven European inspectors held by pro-Russian separatists in eastern Ukraine.
Meanwhile, officials in Ukraine's second-largest city, Kharkiv, say Mayor Hennady Kernes is fighting for his life after being shot in the back by a sniper. Kernes was hit while riding his bicycle on the outskirts of the city.