· 'War on terror' phrase described as misguided · Normality better than rush to legislate, says McNulty

A senior Home Office minister criticised Tony Blair's response to the July 7 bomb attacks last night, saying it had been wrong to suggest that civil liberties had to suffer as a consequence.

Tony McNulty told a fringe meeting in Bournemouth that Britain's legal framework did not need to be altered to fight terror. "Actually the rules of the game had not changed," he said, adding: "I think we have made mistakes since 7/7".

After the attacks that killed 50 people on the London transport network in 2005, Mr Blair advanced a raft of new anti-terror measures, suggesting that Britons would have to accept reductions in their civil liberties as part of the fight against terror. He put forward a 12-point plan, including enforced deportations and a new offence of glorifying terrorism.

But in what seems a major change of heart for the party, Mr McNulty said the phrase "war on terror" was misguided and all violence should be dealt with through normal legal means.

He said: "With the best will in the world, where we are at now as a government means that we are coming round to the view that says, actually, the rules of the game have not changed.

"The more these things are tackled through normality, with some little exceptions at the top, rather than absolutely, by exception, the better. The more any response is rooted in our civil liberties and our human rights with whatever slight tweaks at the top, the better."

He suggested it was unwise to "rush headlong into looking at legislation instantly and with very short shrift", saying it was better to develop a broader counter-terrorist strategy.

Asked about Mr McNulty's comments, the home secretary, Jacqui Smith, said at a separate session:that she and the minister had always been in agreement on the approach to counter terrorism.

"We are completely at one on the way we have to take this forward. Winning over people's hearts and minds and making the case against those who want to carry out attacks on us means we have to think carefully about the arguments you make, and you do not want to further alienate people."

The remarks are striking for Mr McNulty's rejection of any major changes to Britain's anti-terror laws. The government will nevertheless press ahead in the near future with an extension of the period for which suspected terrorists can be held in detention without charge. It is expected that it will seek to double the period of maximum detention, subject to judicial oversight, from 28 to 56 days.