The top U.S. commander in Okinawa said Thursday he believes relocating some U.S. Marine Corps drills to Guam or Saipan will be difficult because those locations are too small.

Lt. Gen. Earl Hailston told reporters after attending a meeting in Tokyo of a Liberal Democratic Party panel on Okinawa that although the idea of relocation is good, Guam and Saipan are not large enough to host drills involving the marine divisions stationed in Okinawa.

Foreign Minister Makiko Tanaka, hoping to lighten Okinawa's burden, proposed the idea of shifting some of the marine drills from Okinawa during her talks Monday in Washington with U.S. Secretary of State Colin Powell.

About 25,000 U.S. service members, including more than 10,000 marines, are stationed in the prefecture.

As for relocating the helicopter operations of the U.S. Marine Corps Futenma Air Station in Ginowan, Okinawa, Hailston said the new facility should be equipped with maintenance buildings and be able to accommodate drills of the same scale as those already being conducted.

A joint civilian-military airport to be built in Nago, northern Okinawa, is to host the copter operations of the Futenma base.

The United States agreed with Japan in 1996 to return the base within five to seven years on condition that its chopper operations are relocated within the prefecture.