No inquiry is under way into why the London bombers were not picked up by the security services, Lord Chancellor Lord Falconer has said.
The government wants to focus on new laws, not inquiries
He said "now is not the time" for an inquiry, but for a decision on what legal steps were needed against terror.
And he denied proposed new anti-terror measures were "slamming the stable door after the horse had bolted".
A newspaper says MI5 had assessed one of the bombers, Mohammad Sidique Khan, but decided he was not a threat.
The Sunday Times said the 30-year-old teaching assistant had been subject to a routine threat assessment when his name cropped up during an investigation last year.
PLANNED NEW LAWS
Outlawing "acts preparatory to terrorism"
New offence of indirect incitement to commit terrorist acts
New law for those providing or receiving terrorist training
However, officers apparently decided that as he was only "indirectly linked" to that investigation, he posed no threat and no action was taken.
Khan, from Dewsbury, West Yorkshire, killed himself and six other passengers in the Edgware Road bombing on the London underground.
Hasib Hussain, 18, from Holbeck, Leeds was responsible for the Number 30 bus bombing, in which 13 people died; Shehzad Tanweer, 22, from Beeston in Leeds for the Aldgate Tube blast, which killed six, and Germaine Lindsay, 19, from Aylesbury, Buckinghamshire, for the King's Cross Tube explosion in which 26 people were killed.
The London bombings did not mean that the intelligence and security services had failed or that existing laws were wrong, Lord Falconer said.
"We have got to learn the lessons and that is why we are bringing forward these new laws. Now is not the time for any form of inquiry," he said.
"I think all the political parties are agreed that the right course at the moment is to focus on what further steps need to be taken in relation to the law but also getting to the root of that evil ideology that is driving this terrorism."
The new anti-terror laws proposed by the government are due to be discussed by Home Secretary Charles Clarke and his opposition counterparts on Monday.
The new Anti-Terrorism Bill - in train before the London attacks - is expected in the autumn and the legislation could be on the statute books by next summer.
Mr Clarke has already outlined details of the plans in a letter to Tory David Davis and Liberal Democrat Mark Oaten, in an attempt to gain consensus.
The planned new offences would outlaw "indirect incitement" and "acts preparatory" to, and "providing or receiving training" in terrorism.
Lord Falconer told BBC News that under the new laws, people "attacking the values of the West" and "glorifying the acts of suicide bombers" would be imprisoned for "long periods" and "deported wherever possible".
But no law could stop terrorism altogether, he added.
"The evil ideology driving this is getting to the hearts and minds of a very small number of people," Lord Falconer said.
"We need to be effective in dealing with them... to make it absolutely clear there will be no compromise."
Shadow home secretary David Davis said he hoped for "a pretty constructive outcome".
The government had "done a good job in terms of crystallising what we are trying to do to stop people inciting young men, or anybody for that matter, to terrorism", he added.
Mr Davis also called for additional proposals to allow phone taps and other intercept evidence in court.
Labour former cabinet minister Clare Short said it was vital that the laws did not prevent people discussing the political situation.
She warned that the prime minister's wife Cherie Blair could face prosecution if anti-incitement laws were not carefully drafted.
Mrs Blair apologised three years ago after saying some young Palestinians felt they had "no hope" but to blow themselves up.
"The problem is going to be in finding the right words and implementing it in a way which is really dealing with people who are inciting and not preventing honest discussion of the underlying causes of this horrendous political situation the world is in now," said Ms Short.
Lord Falconer dismissed her concerns.
"The proposal is that indirect incitement should consist of statements made with the intention of encouraging other people to commit terrorist acts.
"That most certainly is not the sort of thing that Clare Short is referring to."