Angela Merkel says can only end Syrian war with Russia's help

German Chancellor Angela Merkel said on Thursday that it would be possible to end to the civil war in Syria only with the help of Russia, which this week launched air strikes in the war-torn country.

Speaking of the refugee crisis, Merkel said it was necessary to tackle the issues causing people to flee their homes.

"That's particularly true of Syria, where we have all known for years that there can only be a solution with Russian and not without Russia," Merkel said at speech in eastern Germany to mark the upcoming 25th anniversary of German reunification.

The United States took a different stance, with the White House saying Russia's military actions in Syria risked prolonging the conflict in Syria.

On Thursday, Russian warplanes, in a second day of strikes, bombed a camp run by rebels trained by the CIA, the group's commander said.

Read: Merkel's German conservatives dip to year low on refugee crisis - Poll

Watch: Europe's refugee crisis and Syria situation explained