Former Defence Secretary Donald Rumsfeld has finally confessed he was wrong to claim America knew where Saddam Hussein had stockpiled weapons of mass destruction in the first days after the Iraq invasion.

His inflammatory claim that ‘we know where they are’ was quickly proved to be an empty boast.

But breaking his silence for the first time since being axed by President Bush more than four years ago, Mr Rumsfeld made no apology for his controversial handling of the war in Iraq.

In his new autobiography, scheduled for release next Tuesday, the former Pentagon boss said George Bush called him into his office just fifteen days after 9/11 to tell him to start making plans to attack Iraq.

‘Two weeks after the worst terrorist attack in our nation’s history, those of us in the Department of Defence were fully occupied,’ he wrote.

But he said the president was insistent even then that Mr Rumsfeld should come up with ‘creative’ options to topple Saddam.

‘Had the 2003 invasion not taken place, the Middle East would be ‘far more perilous than it is today,’ he added.

The 78-year-old former defence chief – a leading architect of the Iraq war – did, however say he regretted saying ‘stuff happens’ about the early looting in postwar Iraq.

He also concedes it wasn’t diplomatic to blast Germany and France as ‘old Europe’ for failing to support the invasion.

Addressing charges that he failed to provide enough troops for the war, Mr Rumsfeld wrote: ‘In retrospect, there may have been times when more troops could have helped.’

But he insisted that if senior military officers had reservations about the size of the invading force, they never informed him.

Both the New York Times and the Washington Post revealed the highlights of the book after obtaining advance copies.

In a lengthy section on the administration's treatment of wartime detainees, he admitted his biggest regret was not leaving office in May 2004, after the Abu Ghraib prison scandal erupted.

‘Looking back, I see there are things the administration could have done differently and better with respect to wartime detention,’ he acknowledged.

The flinty Washington veteran wrote complimentarily about his old boss in the White House, but criticised Mr Bush’s confused decision-making over national security matters.

He complained meetings often ended without any iron cast decisions being made.

He is more characteristically forthright in criticising former secretaries of state Colin Powell and Condoleezza Rice.

Mr Powell is chided for rebelling against the Bush political doctrine and taking swipes at Mr Rumsfeld through the media.

While Ms Rice is portrayed as an ineffectual national security adviser who fruitlessly pursued diplomatic engagement with traditional foes like Syria, Iran and North Korea, his sharpest criticism is aimed at Paul Bremner, the one-time civilian director of the US occupation of Iraq who ‘inadvertently stoked nationalist resentments and fanned the embers of what would become the Iraqi insurgency.’

More than 60 per cent of the 800-page memoir revolves around his six-year stint as the Bush administration’s Defence Secretary.

Writing about his personal life, he speaks tenderly about the battle with drug addiction fought by two of his three children – son Nick and daughter Marcy.