Tony Blair has made apologies about aspects of the Iraq War for the first time and has said there are ‘elements of truth’ in the theory that the invasion helped feed the rise of Isis.

In a TV interview with CNN, the former Prime Minister said he was sorry that the intelligence behind the decision to attack Saddam Hussein’s regime in 2003 was wrong, and admitted there had been mistakes in the planning of the operation.

He had been asked how he felt about the failure to find weapons of mass destruction in Iraq as he took questions from American political broadcaster Fareed Zakaria in an interview due to be broadcast by CNN Europe on Sunday.

Tony Blair meets troops as he arrives in Basra for a visit to British soldiers in Iraq (AFP)

It is as part of a longer documentary, Long Road To Hell: America In Iraq, set to be screened on Tueday.

With the cameras rolling, Mr Zakaria asked Mr Blair: “Given that Saddam had no WMDs, was the war a mistake?”

He replied: “I apologise for the fact that the intelligence we received was wrong. I also apologise, by the way, for some of the mistakes in planning, and certainly, our mistake in our understanding of what would happen once you removed the regime. But I find it hard to apologise for removing Saddam.”

The Iraq War: A timeline Show all 16 1 /16 The Iraq War: A timeline The Iraq War: A timeline 11 September 2001 Terrorists belonging to al-Qaeda use hijacked aeroplanes to kill 2,996 people in attacks on the east coast of the US. AP The Iraq War: A timeline 12 September 2001 Tony Blair promises George W Bush that the UK will support the US, whatever the President decides to do. AFP/Getty Images The Iraq War: A timeline 25 March 2002 Jack Straw, Foreign Secretary, warns Blair that invading Iraq would be legally dubious. Getty Images The Iraq War: A timeline June 2002 Tony Blair asks defence officials to outline options for UK participation in military action against Iraq. afp/getty images The Iraq War: A timeline 24 September 2002 The government publishes a dossier about the threat from Iraq’s weapons of mass destruction. A foreword by Tony Blair states that Saddam Hussein’s “military planning allows for some of the WMD to be ready within 45 minutes of an order to use them”. It is subsequently alleged that this dossier was “sexed up” for political reasons. Getty The Iraq War: A timeline 2 October 2002 Congress authorises President Bush to use military force against Iraq. Getty The Iraq War: A timeline 8 November 2002 UN Security Council passes resolution 1441, insisting that weapons inspectors be allowed back into Iraq and calling on the regime to give up its WMD or face the consequences. Simon Walker/AP The Iraq War: A timeline 18 July 2003 David Kelly, an expert in biological warfare, is found dead after being named as the source of quotations used by the BBC’s Andrew Gilligan to suggest that the dossier of September 2002 had been “sexed up”. Lord Hutton is appointed to chair a judicial inquiry into his death. GETTY IMAGES The Iraq War: A timeline 13 December 2003 Saddam Hussein is captured near Tikrit, after nine months in hiding. REUTERS The Iraq War: A timeline 2 March 2004 Bombings in Baghdad and Karbala kill nearly 200 people: the worst attacks since the fall of Saddam. Getty Images The Iraq War: A timeline 14 September 2005 Bombs in Baghdad kill 160 people and injure more than 500. EPA The Iraq War: A timeline 30 December 2005 Saddam Hussein is executed. Getty Images The Iraq War: A timeline 28 May 2009 The last British combat troops leave Iraq. Getty Images The Iraq War: A timeline 24 November 2009 The Chilcot inquiry holds its first public hearing. Getty The Iraq War: A timeline 2 February 2011 The Chilcot inquiry holds its final public hearing. AFP/Getty Images The Iraq War: A timeline 21 January 2015 Sir John Chilcot confirms that his report will not be published before the general election in May 2015. Getty Images

Mr Blair’s comments led to questions as to why he had chosen to be so candid to a US network before making such comments to British broadcasters or newspapers. The timing of the interview has been noted by critics, with the long-awaited findings of the Chilcot inquiry into the conflict due to be made public in the coming weeks.

The war led to large scale public protests and rebellions against Mr Blair in the Labour Party. Saddam Hussein was toppled but up to 500,000 people are said to have been killed in war-related deaths from 2003.

In his CNN interview, Mr Blair, who resigned as Prime Minister in 2007, was asked how he felt about being sometimes branded a “war criminal” by his opponents, and how it had changed the way people viewed his time in Downing Street. He responded by comparing the invasion with inaction in Syria, claiming the West and Europe had stood back while hundreds of thousands of people had been killed.

Tony Blair holding a joint press conference with President George W. Bush in the Rose Garden of the White House, his final visit before he resigned in June 2007 (Rex)

He added: “By the way, I always point out to people, I did actually win an election after Iraq. But I agree it’s been a huge political problem.”

In another segment, Mr Blair is asked whether the war provoked the growth of Isis, the group which now controls swathes of Iraq and Syria and which is being hit with air strikes from a US-led coalition that includes the UK.

“I think there are elements of truth in that,” Mr Blair said. “Of course, you can’t say those of us who removed Saddam in 2003 bear no responsibility for the situation in 2015.”

In the past, Mr Blair has been less candid about what went wrong. In 2007, he insisted: “I don’t think we should be apologising at all for what we are doing in Iraq.”