The office has been so damaged that it's pretty clear to me that it cannot function

Donald Rumsfeld

Defence Secretary Donald Rumsfeld said such criticisms were "off the mark", but were so damaging that the unit's ability to function effectively had been irreparably compromised.

The office was created following the 11 September attacks on America as part of efforts to combat international terrorism.

On Monday, President Bush pledged that his administration would tell the American people the truth about its foreign policy.

Controversy

Concerns over the unit were raised by members of Congress and officers in the military.

The office became the centre of a controversy following disclosures in the New York Times that it had proposed a campaign to influence international opinion, including the possibility of planting false stories in foreign news media.

Rumsfeld: Criticisms "off the mark"

The move angered many in Washington - in a rare public disagreement within the Bush administration, White House officials aired their misgivings.

But Mr Rumsfeld said the Pentagon had not been and would not be involved in disinformation, adding that the allegations had nonetheless been fatal for the office.

"Notwithstanding the fact that much of the thrust of the criticism and the cartoons and the editorial comment has been off the mark, the office has been so damaged that it is clear to me, it's pretty clear to me that it cannot function," he said.

The bureau was originally set up to oversee such activities as dropping leaflets and broadcasting radio messages in Afghanistan.

But its mandate was still being determined when the disclosures were made.