The First Group of Russian forces, including air force officials from the Eastern Military District, have left Moscow and would join works at the Colorado headquarters in the U.S., military spokesman Alexander Gordeyev told Interfax news agency.

The second delegation would engage in works at the backup headquarters in Alaska, according to Gordeyev.

The aim of the drills is to improve coordination and interaction between the Russian armed forces and the North American Aerospace Defense Command (NORAD) in case of aircraft hijacking.

NORAD is a joint organization of the U.S. and Canada that provides aerospace warning, air sovereignty and defense for the two countries.

The Russian delegation would also visit the U.S. Air Force Academy in Colorado Springs at the invitation of U.S. officials, Gordeyev said.