“LEMON fish with two types of vegetables” followed by “two types of fruit”. That account of the fine cuisine at Guantanamo Bay on which prisoners are dining, which has been “purchased by American taxpayers”, was crafted by Duncan Hunter, the Republican Chairman of the Armed Services Committee in the House of Representatives.

He is one of the fiercest defenders of the prison camp in Cuba in which the US holds detainees in the War on Terror. But the Administration is coming under new pressure to justify the use of the camp.

The Senate Judiciary Committee will hold a hearing today into reports of torture and other abuses. A House committee investigation is likely to follow.

Pressure from abroad has been ignored by the US but as Condoleezza Rice, the Secretary of State, will no doubt hear when she begins a tour of the Middle East on Friday, Guantanamo makes it awkward for the US to promote democracy and respect for law without getting charges of hypocrisy in return.

The new criticism focuses on recent reports of ill-treatment, more than on the fundamental justification for the camp. One trigger has been Time magazine’s publication this week of an 84-page interrogation log leaked from Guanta-namo, recording the treatment of Detainee 63 for 50 days up to January 2003. Mohammed al-Qahtani, one of several people to be dubbed the “20th hijacker”, was refused entry to the US in August 2001, a month before the destruction of the Twin Towers. He was captured in Afghanistan.

The log shows that his treatment was increasingly harsh, to the point where his pulse rate slowed to about 30 beats a minute. According to Time, the log was unclear on whether he gave any useful information. He has never been charged or had a lawyer.

The Pentagon, in a detailed defence, has said that his treatment was always humane and that it used approved interrogation approaches. However, the Pentagon dropped the harshest techniques early in 2003, just after the log ends, after military lawyers challenged them.

The Pentagon added that the results had been valuable, although they had come during a period not covered by the log. The Pentagon and the Justice Department are investigating the case.

The Pentagon has also released details this month of five incidents in which guards at Guantanamo mistreated the Koran, including stepping on it and kicking it. That followed the report by Newsweek magazine that a copy of the Muslim holy book had been flushed down a toilet, which provoked riots in Afghanistan in which 16 died. The magazine retracted the report, saying that it could not substantiate the story. But Muslim leaders are calling for a US apology for the admitted cases.

The passage of time, too, has added to the pressure on the Administration. It is nearly four years since the US began detaining prisoners at the camp without charge. The number of federal lawsuits challenging the detention has grown. Among other lines of attack, lawyers say that there may be as many as six prisoners who were captured before they turned 18 and that the military has tried to conceal the number of juveniles.

There has been new criticism from human rights groups. Amnesty International compared the facility to Soviet Union gulags and Jimmy Carter, the former President, has called on President Bush to shut it down.

The greatest source of pressure is coming from Congress. Harry Reid, the leader of the Senate Democrats, said that the detention had “caused tremendous damage to American credibility around the world and placed our troops at greater risk”.

Unease about Guantanamo is also spreading to Republicans. Chuck Hagel and Mel Martinez, of the Senate Foreign Relations Committee, have called for investigations.

The White House response has been mixed. Dick Cheney, the Vice-President, said that there were no plans to close the camp. But Mr Bush told Fox News that he was looking at all alternatives.

That is the first sign in four years that the Administration might change its mind.

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