A former Labour MP who opposed the Iraq war says he will never understand why Tony Blair backed US president George W Bush.

Derek Wyatt, who represented Sittingbourne and Sheppey between 1997 and 2010, never believed there were weapons of mass destruction (WMDs).

When parliament voted on the issue in March 2003, he decided not to support his own government.

Speaking today after the publication of the long-awaited Chilcot Report, he revealed he and colleagues were told beforehand there were no WMDs.

He said: “A group of us took it upon ourselves to find out more about the situation from [UN weapons inspector] Hans Blix and were informed categorically there were no weapons of mass destruction in Iraq.

“This information was backed up by a Harvard University academic who stated that going to war in Iraq would benefit the Bush and Cheney administration as they had investments in weapons companies.”

The Chilcot Report, which has taken seven years to publish, has found the government failed to exhaust all peaceful options before the invasion.

Mr Wyatt added: “What we will never understand is why Blair supported Bush.

“It ended his career and will be on his gravestone forever.

“We now have very big questions to ask about his government and leadership; I am very angry as this will be with us for at least 20 more years.”

He also criticised the Foreign Office, saying: “It has now got a legacy of errors, caused by backing the wrong side.

“It’s terrifying.”

The 66-year-old believes the invasion caused harm that is still being felt.

“It’s appalling; it is, in my opinion, what caused all of the problems in the Middle East that we are seeing today.

“Just looking at how chaotic it was after the downfall of Saddam Hussain’s regime: we went in completely naked with no clue of how to get out of this situation.”

"I am very angry as this will be with us for at least 20 more years" - Derek Wyatt

As well as the political reasons for opposing the war, which started days after the vote, Mr Wyatt said he also had pressure from his family.

He said: “My daughter said to me ‘dad if you vote for this war, I’ll never speak to you again’.”

It is estimated since the invasion, more than 500,000 people have been killed or injured.

Answering questions today, Mr Blair has accepted responsibility for his choice, saying he made the decision based on intelligence given.

Since Mr Wyatt stepped down ahead of the 2010 general election, he has been involved with multiple charities and organisations including chairing the Royal Trinity Hospice in Clapham and being involved within NISE Nursing and Crowdbnk.