The United States would deploy some 300 carrier-borne helicopters and aerial tankers at the U.S. Marine Corps Air Station Futenma in Okinawa under a plan compiled in 1996 in response to an emergency on the Korean Peninsula, official U.S. documents obtained by Kyodo News showed Thursday.

Under the plan, the U.S. forces would deploy 71 helicopters and aerial tankers at the base in the city of Ginowan in times of peace, and gradually add 142 more aircraft in an emergency. If the emergency escalates into battle, they would send 87 more, including 18 attack helicopters.

While the plan does not clearly show how the military aircraft would be transported from Futenma to the Korean Peninsula, it is likely that they would be moved by large transport planes, according to several experts.

Kensuke Ebata, a military commentator, said the plan shows Futenma is regarded as "the frontline base for sorties."

The Japanese and U.S. governments agreed last year to relocate the Futenma air station to an airfield to be built on a peninsula extending from the U.S. Marine Corps Camp Schwab in Nago, farther north on Okinawa Island, from the densely populated Ginowan.