US President George W. Bush (L) and British Prime Minister Tony Blair walk together from their meeting at the US Embassy in Brussels in this February 22, 2005 file photo. [Photo/Agencies]

The then UK Prime Minister Tony Blair took Britain to war against Iraq in 2003 on the basis of flawed intelligence and failure to communicate with his ministers, according to a massive report on Britain's role in the Iraq war published on Wednesday, seven years after it was commissioned.

The seven volume report, 2.6 million words long and three times as big as the complete works of William Shakespeare, was ordered by Blair's successor as Prime Minister, Gordon Brown in 2009.

Blair, who was Labour Party prime minister from 1997 to 2008, took Britain to war in Iraq as part of a US-led coalition, ostensibly because Iraqi leader Saddam Hussein had weapons of mass destruction. In the 2003 invasion and aftermath which toppled Saddam, 179 British soldiers were killed.

In the event, no evidence of weapons of mass destruction, a euphemism for chemical or nuclear weapons, was found.

Blair has repeatedly been accused by UK politicians from all parties of being too close to the then US president, George W. Bush.

The report, headed by civil servant Sir John Chilcot, found that there had been serious intelligence failures, and a string of bad judgments made by senior officials.

Blair reacted to the report by saying his decision to invade along with US-led forces was "taken in good faith and in what I believed to be the best interests of the country."

Prime Minister David Cameron told the House of Commons today "Clearly, we need to learn the lessons of this report."

Opposition leader Jeremy Corbyn, who in the past has called for Blair to stand trial for war crimes, said the invasion had been on "false pretexts, and has long been regarded as illegal. The war fuelled and spread terrorism in the region."

Blair, who has built up an international consulting firm with many government contacts, including China and Saudi Arabia, said he did not believe the removal of Saddam Hussein "is the cause of terrorism we see today".

But he added in a statement after the report was released: "I will take full responsibility for any mistakes."

An estimated 150,000 Iraqis, mainly civilians, were killed in the invasion and its aftermath, and over one million made homeless.

Contact the reporter on chris@mail.chinadailyuk.com