Defense Agency chief Gen Nakatani on Tuesday denied that Maritime Self-Defense Force vessels would join the USS Kitty Hawk battle group in the Indian Ocean for expected U.S.-led military retaliation against terrorist attacks in the United States.

"We are not considering (MSDF ships) joining the Kitty Hawk fleet and going to the Indian Ocean together," he said at the day's regular news conference.

Prime Minister Junichiro Koizumi last week announced that Japan will dispatch MSDF ships to gather information, as one of the seven measures the nation will take in response to the terrorism.

Some Japanese media have said MSDF ships deployed for that purpose are likely to join the Kitty Hawk, which left the Yokosuka Naval Base in Kanagawa Prefecture on Friday for an undisclosed destination. The reports suggested that doing so would be a breach of the current interpretation of the Constitution, which prohibits collective defense.

Nakatani also denied media reports that the agency had decided to dispatch an MSDF fleet escort force including an Aegis-equipped destroyer, from its Sasebo Base in Nagasaki Prefecture as early as Thursday. He said the agency will not make a decision on deployment before discussing the matter with the prime minister and Cabinet secretaries.