The United States will conduct training flights of Osprey aircraft over the main islands next week, Lt. Gen. Samuel Angelella, the top commander of the U.S. military in Japan, said Thursday.

It will be the first time the controversial aircraft will conduct training flights over the main islands. Twelve were deployed at the Futenma base in Okinawa Prefecture last fall.

"Next week we will be flying the aircraft from Okinawa to do training elsewhere in Japan," Angelella told a news conference at the Foreign Correspondents' Club of Japan in Tokyo.