More U.S. sanctions likely if Russian actions in Ukraine continue

WASHINGTON (Reuters) - The United States prepared to step up sanctions against Moscow if pro-Russian military actions in eastern Ukraine continue, a senior U.S. envoy said on Sunday, but it is unclear whether new measures will win European support or slow the Russian-backed separatist revolt.

The next round of U.S. sanctions, which would be the fourth imposed since the Ukraine crisis began, is likely to target Russians close to Putin as well as Russian entities, three sources familiar with the discussions said on Sunday.