Home Secretary Charles Clarke has said there is no evidence the attacks on London were carried out because of the UK's role in the Iraq war.
Mr Clarke said catching the perpetrators was the number one issue
He said the bombers wanted to destroy the "very essence of our society".
Mr Clarke said: "There is no evidence [it] had anything to do with the Iraq war... of course it may have done and we'll have to see."
Anti-war MP George Galloway has said Londoners "had paid the price" of the wars in Iraq and Afghanistan.
Mr Clarke told the BBC that any conflicts or wars could increase tensions, but said those tensions could exist anyway.
He said: "The fact is that the people who make these kind of attacks are about destroying the very essence of our society: our democracy, our media, our multicultural society and so on.
"That's not about Iraq or any other particular foreign policy issue, it's about a fundamentalist attack on the way we live our lives."
Nothing ruled out
Mr Clarke said the prime issue a day after the attacks, which claimed more than 50 lives and left another 700 injured was to catch the bombers because of the danger they might carry out more attacks.
He said it was very possible the bombings were the work of Islamic extremists but added "no hypothesis has been ruled out or confirmed" including "some elements of Irish terrorism".
On Thursday Mr Galloway said Londoners had paid the price for Iraq and Afghanistan.
He told the Commons it was the US-led coalition's actions in Afghanistan, Iraq and Guantanamo which had inflamed hatred of the West in the Muslim world.
That prompted Adam Ingram to accuse him of "dipping his poisonous tongue in a pool of blood".
The armed forces minister added that Mr Galloway's comments were "disgraceful".
Earlier Mr Galloway said he was absolutely clear the bombings had been carried out by Islamic extremists inspired by Osama Bin Laden's world outlook.
He argued that the bombings had not come out of the "clear blue sky" - the background was the invasion of Afghanistan, Iraq, photographs of abuses by US troops at Abu Ghraib prison and the continuing confinement of people by America at Guantanamo.
Mr Galloway said the West was in danger of making the same mistakes over and over again, continuing with "war and occupation as the principal instrument of our foreign and defence policy".
He added: "And if we do then some people will get through and hurt us as they have hurt us today."
Paid the price?
Mr Galloway who was expelled from the Labour Party over his outspoken comments on the Iraq war, linked the deaths of people in London to the deaths of those in Falluja at the hands of coalition forces.
Earlier, in a statement, the MP said: "The loss of innocent lives, whether in this country or Iraq, is precisely the result of a world that has become a less safe and peaceful place in recent years.
"We have worked without rest to remove the causes of such violence from our world.
"We argued, as did the security services in this country, that the attacks on Afghanistan and Iraq would increase the threat of terrorist attack in Britain.
"Tragically Londoners have now paid the price of the government ignoring such warnings."