Planning for the 2003 invasion of Iraq was inadequate and not enough troops were sent to ensure post-conflict security, the former US diplomat who led the civilian occupation authority after the war has told a British inquiry.
Paul Bremer, who governed Iraq's Coalition Provisional Authority (CPA) for 13 months after President Saddam Hussein was toppled, said there had been a serious miscalculation by those responsible for planning the invasion.
"It is impossible to exaggerate the difficulties created by the chronic under-resourcing of the CPA's efforts," Mr Bremer said in a statement, made public today, to an inquiry examining Britain's role in the war.
"This problem, and the fact that the coalition was unable to provide adequate security for Iraqi citizens, pervaded virtually everything we did, or tried to do, throughout the 14 months of the CPA's existence."
As head of the CPA, Mr Bremer was then-President George W Bush's top official in Iraq from May 2003 until June 2004 when the United States returned sovereignty to Iraqi authorities.
The Pentagon has previously acknowledged that Mr Bremer's request in 2004 for about 500,000 extra troops was turned down by then-Defence Secretary Donald Rumsfeld.
Critics say the Pentagon deployed too few US soldiers to maintain order, restore essential services such as power and water and combat an escalating insurgency.
"It was evident to me from the start that the pre-war planning had been inadequate, largely because it was based on incorrect assumptions about the nature of the post-war situation on the ground in Iraq," Mr Bremer's statement said.
"Even before I left for Baghdad, I was concerned that the coalition had insufficient troops to carry out its primary duty of providing security for the Iraqi people."
Mr Bremer said the failure to check the violence and looting after Saddam was ousted cost Iraq's economy some $12 billion (€9.7 billion). But he said of greater damage was the message it gave Iraqis that the coalition could not provide basic security.
He again defended his decision to disband the Iraqi army after the war, which many experts consider was a mistake causing many ex-soldiers to join the insurgency, and to ban members of Saddam's Baath Party from government posts.
"The myth that de-Baathification collapsed the Iraqi government is simply unsupported by the facts," he said.
"No doubt some members of the former army may have subsequently joined the insurgency. But if they did so, for most of them it was not because they had been denied an opportunity to serve their country again. It was because they wanted to install a Baathist dictatorship."
The British public inquiry, headed by former civil servant John Chilcot, said it had questioned a number of US officials this month including Mr Bremer, but only provided details of those who had agreed to have their names released publicly.
The five-person panel began its work last year and has already questioned former prime ministers Gordon Brown and Tony Blair, who was Mr Bush's strongest ally in the war.
Its hearings, which ceased during the recent British election, are due to resume in London in the summer.
Reuters