The war against terrorism is being damaged by the US continuing to run its Guantanamo Bay detention centre, an influential committee of MPs has said.
Some inmates have been at the detention camp since 2002
The Commons foreign affairs committee urged ministers to make UK opposition to the camp "loud and public".
But Tony Blair refused to go further than his previous stance on the camp, telling reporters it was "an anomaly" which should come to an end.
He urged people to remember the terror attacks which prompted its creation.
Earlier, Lord Chancellor Lord Falconer said the UK would never have opened the camp.
And Attorney General Lord Goldsmith said everyone, including terror suspects, were entitled to a fair trial.
There are currently about 490 terror suspects being held without trial at the camp, which opened in 2002.
In their annual human rights report, the committee of MPs says the continued use of the centre "outside all legal regimes diminishes the USA's moral authority and is a hindrance to the effective pursuit of the war against terrorism".
"We recommend that the government make loud and public its objections to the existence of such a prison regime," say the MPs.
Asked why he would not be more forthright in condemning the camp, Mr Blair said: "I have said why I think Guantanamo is an anomaly and should come to an end.
"I also think, however, it is important that we never forget the context in which this has happened, which is the context of the war in Afghanistan and the reason for that was the slaughter of 3,000 innocent people on 11 September.
"Now, it is important of course that we pursue the action against terrorism, maintaining absolutely our commitment to proper civil liberties and human rights.
"But it's also important that we remember those people that died in that terrorist act and have some understanding therefore of the huge amount of anger there is in American over what happened there."
Foreign Secretary Jack Straw told reporters that shouting was not the most effective method of diplomacy.
Mr Straw said it was as a result of his diplomacy that all the British citizens held at Guantanamo Bay were released.
Earlier, Lord Falconer told BBC Radio 4's Today programme the UK would not have set up the Guantanamo centre.
Lord Falconer said the UK stood by the principles of human rights.
Lord Goldsmith wants the law to cover everybody
"America is our ally, we are not responsible for all that our ally does," he said.
A report for the United Nations last week said aspects of the regime at the camp amounted to torture.
Northern Ireland Secretary Peter Hain also last week said the camp should be closed.
Lord Goldsmith negotiated the release of nine Britons who were held at the camp, although three former UK residents are asking the High Court to make the UK petition for their release.
In a speech at the London School of Economics, the attorney general stressed the importance of giving everybody a fair trial.
"There should be in modern society no outlaws; no people to whom the law does not apply... and to whom therefore anything can be done," he said.
Lord Goldsmith also welcomed moves by Home Secretary Charles Clarke to look seriously at whether intercept evidence in these cases could be used in court.