Kerry voices concern to Russian counterpart on Ukraine fighting

U.S. Secretary of State John Kerry speaks during a Reuters Newsmaker event on the nuclear agreement with Iran, in New York August 11, 2015. REUTERS/Brendan McDermid

WASHINGTON (Reuters) - U.S. Secretary of State John Kerry on Thursday expressed "gave concern" to his Russian counterpart about a sharp rise in separatist attacks in eastern Ukraine and urged an immediate cease-fire, the State Department said.

Kerry's comments, in a telephone call with Russian Foreign Minister Sergei Lavrov, reflected growing U.S. worries about the increasing violence between Ukrainian government forces and pro-Russian rebels.