"Creation of a broad alliance, including Russia, to fight international terrorism in Syria and Iraq is still our goal," Seibert said.
He added that the downing of Russia's Su-24 aircraft caused concerns in Berlin and called on Moscow and Ankara to reduce the tensions resulting from the accident.
On Tuesday, a Russian Su-24 jet crashed in Syria. Russian President Vladimir Putin said that the plane was downed by an air-to-air missile launched by a Turkish F-16 jet over Syrian territory, falling 4 kilometers (2.5 miles) from the Turkish border. Putin described the Turkish attack as a "stab in the back" carried out by "accomplices of terrorists."