The US Defense Department Saturday invoked authority to use civilian planes for transporting troops and military hardware to the Gulf area.
"This measure is necessary due to increased operations associated with the buildup of US forces in the Persian Gulf region," the Pentagon said in a statement.
The authority covers 22 US airlines and their 78 commercial aircraft -- 47 passenger aircraft and 31 wide-body cargo aircraft,but the US Transportation Command, for the time being, will activate only the 47 passenger aircraft, according to the statement.
A US Transportation Command spokesman said the airlines all volunteered to participate in the contractual arrangement and are being paid for the use of their aircraft.
During the 1991 Gulf War, the Pentagon invoked the similar authority to ferry troops and military equipment abroad.
The number of US troops in the region now stands at about 113,000, and is expected to reach about 150,000 by Feb. 15, US defenseofficials said.