The Maritime Self-Defense Force commissioned its largest-ever helicopter carrier Wednesday in Yokohama as officials denied that the massive vessel could be used as a conventional aircraft carrier or represents a prototype for one in the future.

The 248-meter Izumo, which has a displacement of 19,500 tons and is officially classified as a "helicopter destroyer," resembles an aircraft carrier at first glance.

It has a flat flight deck with a single superstructure, which contains the bridge. The deck is large and robust enough to permit the operation of Osprey tilt-rotor aircraft, MSDF officers said.