His statement seemed likely to add to an embarrassing rift between London and Washington -- allies in the war to overthrow Saddam Hussein -- over the way intelligence was used in the run-up to the conflict.

The issue is likely to cloud talks in Washington on Thursday when British Prime Minister Tony Blair -- en route to East Asia -- sees US President George W. Bush and makes a special address to Congress.

Straw, speaking on BBC radio, stood by Britain's claim, which was contained in a controversial 50-page dossier on Saddam's pursuit of nuclear, biological and chemical weapons issued last September.

"We believe in the intelligence which was behind the claims made in the September 24 dossier, yes," he said on the Today current affairs program when asked if the intelligence on Niger was still valid in British eyes.

He added, however, that Britain was not at liberty to tell the United States where it got the information, because it had come from "foreign intelligence sources".

"It just happens to be the rules of liaison with foreign intelligence sources that they own the intelligence. The second intelligence service does not and therefore is not able to pass it on to the third party."

The Italian government on Sunday denied reports that its intelligence services handed the United States and Britain documents indicating that Iraq was seeking uranium from Niger for a nuclear weapons programme.

The Financial Times reported Monday that Britain received information that Iraq was seeking to acquire uranium from Niger from two sources, thought to be France and Italy, which explained why it was included in the September dossier despite being told the US Central Intelligence Agency (CIA) had "reservations" about its inclusion.

Bush included the British reference to Niger, with attribution to British intelligence, in his State of the Union address last January in which he made his case for war on Iraq.

But last Saturday, CIA director George Tenet cast doubt on the accuracy of the claim, saying it should never have been included in Bush's speech.

Blair was Bush's staunchest ally on Iraq, but since combat was declared over on May 1 US and British forces have yet to unearth hard proof of Saddam's weapons of mass destruction -- let alone the man himself.

On Monday Blair said Britons should be "proud" of having helped the United States overthrow Saddam Hussein's regime in Iraq.

"When we have over the past couple of days taken the first steps for Iraqi people actually to take control of their own lives, and we have the United Nations talking about 300,000 people and mass graves, then I believe we should be proud that Saddam has gone, glad that he has gone," he said.

"I have no doubt at all that in the future, whatever the differences have been in the past, we can reconstruct Iraq as a stable and prosperous country and the world will be a more secure place as a result," Blair told a gathering of fellow center-left world leaders.

"We should be proud as a country of what we have done."

Britain and the United States are also at odds over US plans to put two British citizens -- now held at the US base in Guantanamo Bay, Cuba -- on trial for terrorism before a military commission.

"It is not acceptable for them to be tried if they are not given basic principles of human rights and fair trial," Straw said. "So we are in a process of discussions with the US authorities about a range of options."

Those options range from trial in Britain through to trial by the US military commission so long as it is consistent with the "rules of justice and human rights", he said.

WAR.WIRE