"We need very much Russia's assistance in resolving such issues as Iran, Syria," Steinmeier said on the sidelines of a G7 ministerial meeting in the German city of Lubeck.
"These conflicts are impossible to resolve without Russia's participation," Steinmeier stressed.
Moscow hosted two rounds of intra-Syrian talks, involving envoys of both the government and the opposition. The latest round took place last week and resulted in an unprecedented breakthrough, according to Syrian UN envoy Bashar Jaafari.
As one of the UN Security Council permanent members, Russia is part of the P5+1 group, which also comprises the United States, the United Kingdom, France, China and Germany. Earlier this month, the group reached a framework for a comprehensive deal with Iran guaranteeing peaceful nature of Tehran's nuclear program.