The Japan-U.S. security alliance should be upgraded to contribute to "international peace," not just security in the Asia-Pacific region as currently defined under the bilateral security pact, Defense Agency chief Yoshinori Ono said Tuesday.

Ono added, however, that no such review is formally being discussed between the two countries.

"The Japan-U.S. alliance must be taken in a global context," he said. "The maintenance of international peace has become a new mission (of military forces) in a new security environment and Japan will have to do what it has to do."

Ono made the remarks, which he described as his "personal views," as Japan seeks to play a more active global role and as Tokyo and Washington discuss a realignment of the U.S. military in Japan as part of Washington's global review of its military posture.

The 1960 Japan-U.S. security pact authorizes the U.S. presence to maintain security in Japan and the Far East.

A joint declaration issued by then Prime Minister Ryutaro Hashimoto and President Bill Clinton effectively expanded the scope of the alliance to cover security in the Asia-Pacific region.

Critics have said the U.S. military presence here violates the security treaty because American troops and aircraft sent from bases in Japan have played key roles in wars waged far from Japan, such as the 1991 Gulf War and the recent war in Iraq.

Ono did not specify whether he thinks the security pact should be revised to allow the U.S. presence beyond the stated purpose of maintaining security in Japan and the Far East, but said "there must be no ambiguity" in a new U.S. military posture in Japan.