Jimmy Carter, the former US president, has strongly criticised George Bush and Tony Blair for waging an unnecessary war to oust Saddam Hussein based on "lies or misinterpretations". The 2002 Nobel peace prize winner said Mr Blair had allowed his better judgement to be swayed by Mr Bush's desire to finish a war that his father had started.
In an interview with The Independent on the first anniversary of the American and British invasion of Iraq, Mr Carter, who was president from 1977 to 1981, said the two leaders probably knew that many of the claims being made about Saddam Hussein's weapons of mass destruction were based on imperfect intelligence.
He said: "There was no reason for us to become involved in Iraq recently. That was a war based on lies and misinterpretations from London and from Washington, claiming falsely that Saddam Hussein was responsible for [the] 9/11 attacks, claiming falsely that Iraq had weapons of mass destruction. And I think that President Bush and Prime Minister Blair probably knew that many of the allegations were based on uncertain intelligence ... a decision was made to go to war [then people said] 'Let's find a reason to do so'."
Before the war Mr Carter made clear his opposition to a unilateral attack and said the US did not have the authority to create a "Pax Americana". During his Nobel prize acceptance speech in December 2002 he warned of the danger of "uncontrollable violence" if countries sought to resolve problems without United Nations input.
His latest comments, made during an interview at the Carter Centre in Atlanta, are notable for their condemnation of the two serving leaders. It is extremely rare for a former US president to criticise an incumbent, or a British prime minister. Mr Carter's comments will add to the mounting pressure on Mr Bush and Mr Blair.
Mr Carter said he believed the momentum for the invasion came from Washington and that many of Mr Bush's senior advisers had long ago signalled their desire to remove Saddam by force. Once a decision had been taken to go to war, every effort was made to find a reason for doing do, he said.
"I think the basic reason was made not in London but in Washington. I think that Bush Jnr was inclined to finish a war that his father had precipitated against Iraq. I think it was that commitment of Bush that prevailed over, I think, the better judgement of Tony Blair and Tony Blair became an enthusiastic supporter of the Bush policy".
Mr Carter's criticisms coincided with damaging claims yesterday from a former White House anti-terrorism co-ordinator. Richard Clarke said that President Bush ignored the threat from al-Qai'da before 11 September but in the immediate aftermath sought to hold Iraq responsible, in defiance of senior intelligence advisers who told him that Saddam had nothing to do with the conspiracy.
With an eye to November's presidential elections, Mr Bush sought on Friday to use the anniversary of the Iraq invasion to say that differences between the US and opponents of the war belonged "to the past".
Speaking at the White House, he told about 80 foreign ambassadors: "There is no neutral ground in the fight between civilisation and terror. There can be no separate peace with the terrorist enemy."
But in the US and Britain, and elsewhere, there is growing anger among people who believe the war in Iraq was at best a deadly distraction and at worst an impediment to the war against al-Qa'ida - diverting resources and energy from countering those groups responsible for attacks such as the train bombings in Madrid.
Over the weekend millions of anti-war protesters poured on to the streets of cities around the world to call for the withdrawal of US-led troops from Iraq. It was estimated that in Rome - which saw the biggest crowds - up to one million turned out.
Mr Carter, 79, has recently published a novel. The Hornet's Nest is centred on America's revolutionary war against the British. That period had many lessons for the present day, Mr Carter said.