THE United States was “straining at the leash” to start war with Iraq even before Tony Blair secured the backing of the Commons for military action in the most important vote of his life on March 18, The Times can reveal today.

Shortly after Mr Blair finished his speech to MPs, and several hours before he won a majority for war, the Americans were preparing to put their special forces into action.

In the event, hostilities began the following night with the “decapitation” attempt by American forces to kill Saddam Hussein in Baghdad.

In a book based on his time in Downing Street in the run-up to the war and during the hostilities, Sir Peter Stothard, the former Editor of The Times, tells of a conversation between Alastair Campbell, Mr Blair’s director of communications, and an unnamed White House official just after Mr Blair’s speech and as potential rebels queued up for a final chat with the Prime Minister.

Mr Campbell, taking the call in the Commons office of Mr Blair’s parliamentary private secretary at about 3pm, appeared shocked. “What are you saying?” he asked the official, believed to be his White House opposite number Dan Bartlett. The reply is not known. “Well, if you could just hold it till we’ve got this out of the way, it would be very helpful,” Mr Campbell replied. The “this” is quite clearly the Commons vote which, had he lost, would have been the end of Mr Blair as Prime Minister.

British and American special forces had been on the borders of Iraq for some time, but what worried Mr Campbell was the presence of journalists with the America forces.

The Times has learnt that the conversation was about the alert to journalists that they were being mobilised. Mr Campbell was concerned that the moment US journalists were told forces were preparing to move, word would get to Britain during the Commons debate.

If any action became public before Mr Blair had secured Commons backing, it could have had a damaging effect.

Mr Campbell said: “Your special forces? They have journalists with them?” Sir Peter, who was given unique access to the Downing Street machine at the height of the conflict, writes: “Campbell is not easy to surprise. He looks seriously surprised now.”

The communications chief then added: “Do you mean in the middle of the night our time? . . . Just bear in mind that we have to be in Brussels on Friday and the Prime Minister will want to be here when . . .” He sighed, went to Mr Blair’s office and slammed the door.

Sir Peter recalled yesterday: “The conversation ended with Alastair joking: “I see, so it’s a case of ‘now we have got the British peaceniks in line, we can go’.”

The episode underlines more starkly than ever the impatience of the Americans to begin war and the influence that Britain had on timing.

Mr Blair, The Times understands, told President Bush that there should be no overt action by either country until the Commons vote.

Mr Campbell’s words show how worried he was that action by American special forces — which unlike the British had journalists “embedded” with them — could become public even before the crucial Commons vote was taken.

Many in Downing Street were irritated at the “gung-ho” attitude of the Americans, and the “decapitation” attempt which started the war on the following night took everyone in No 10, including Mr Campbell, by surprise. Downing Street has admitted that Mr Blair was told only shortly before it happened.

Today’s disclosure will give added ammunition to war critics who say that Mr Blair had no choice but to dance to Mr Bush’s tune.

Only a week earlier Donald Rumsfeld, the US Defence Secretary, had provoked outrage when he suggested that Washington would go it alone if Mr Blair did not secure parliamentary backing for war. Sir Peter reveals that it had taken two calls from Mr Blair to Mr Bush to establish that Mr Rumsfeld was “only trying to help”.

The book, 30 Days: a Month at the Heart of Blair’s War, shows that No 10’s anger with the press in general, and the BBC in particular, over coverage of the war was fierce.

Throughout the account figures including Mr Campbell, John Prescott and John Reid, then Labour chairman, berate the press. On March 21, after news of the first British deaths in the conflict, Jack Straw, the Foreign Secretary, returned to No 10 from a Today programme interview and said: “They allowed me to speak. They were almost respectful.”

Mr Campbell retorted: “Even the BBC can be respectful when people are dead.”

Sir Peter describes Mr Campbell as the man to whom Mr Blair still speaks the most. “It is when the two are alone together that the Prime Minister’s face is most the face of a friend at a party, an actor offstage, a person who is not Prime Minister. Campbell has a well-founded reputation for low stratagems on his master’s behalf, but he is the one who dares to speak most fiercely and directly to Tony Blair.”

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