Britain's chief legal official, Lord Chancellor Charles Falconer, said the deadly attacks in London on 7 July showed the government must act against people "who are encouraging young men who are becoming suicide bombers."
"I think there is a very widespread sense in the country subsequent to 7 July that things have changed. A new balance needs to be struck. It needs to be a lawful balance but it needs to be an effective balance," he told British Broadcasting Corporation radio.
Since the bombings on three underground trains and a bus, which killed 52 people and four suspected attackers, Blair's government has been trying to build support among political opponents and Muslim leaders for new anti-terrorism legislation.
On Friday, the prime minister announced proposals to deport foreign nationals who glorify acts of terror, bar "radicals" from entering Britain, close down mosques linked to extremism, ban certain Islamic groups and, if necessary, amend human rights laws.
But the government's new plans appear to have cracked the spirit of consensus.
Liberal Democrat leader Charles Kennedy warned the measures could alienate the law-abiding majority of Britain's 1.8 million Muslims and inflame tensions.
"A fundamental duty, a responsibility on all of us, whether government or nongovernment, is to uphold the rule of law and the safety of the citizen," he said. "But alongside that, of course, is to uphold civil liberties and the right to free speech. It is getting that balance right that will be very important," he told BBC radio.
British Muslims deem the
A British Muslim group called the Islamic Forum Europe warned the measures could jeopardise national unity in Britain.
"If these proposed measures are allowed to see the light of day, they will increase tensions and alienate communities. The measures are counterproductive and will encourage more radicaliSation," said forum President Muslih Faradhi.
"Many Muslims will perceive our prime minister as playing into the hands of the terrorists."
He also criticised the government's plans to ban Hizb ut-Tahrir, a Muslim group that calls for the formation of an Islamic caliphate and is banned in several countries in Central Asia.
Supporters insist it is a nonviolent group persecuted by corrupt governments.
"It will give a green light to despotic leaders in the Muslim world to silence political dissenters"
Islamic Forum president
"Proscribing it will be counterproductive," said Faradhi. "It will give a green light to despotic leaders in the Muslim world to silence political dissenters."
The founder of the al-Muhajirun (Muslim Immigrants) Group in Britain, Shaikh Omar Bakri, has said Muslim youth will view the new measures announced by Blair as similar to those adopted by former Iraqi President Saddam Hussein as well as other Arab leaders.
Bakri sharply criticised Blair's proposals which give the government wide powers to deport anyone who advocates hatred and terrorism.
However, Bakri has ignored accusations that he preaches mainly to a group of extremists in London.
Suspects in court
Meanwhile, three men were scheduled to appear in court on Saturday charged with failing to disclose information about the whereabouts of a suspect in the failed 21 July London bomb attacks.
The Metropolitan Police said Shadi Sami Abdel Gadir, 22, Omar Almagboul, 20, and Mohamed Kabashi, 23, were charged under the Terrorism Act with withholding information that they "knew or believed might be of material assistance in securing the apprehension, prosecution or conviction" of a terrorist suspect.
Three other people already face similar charges, including the wife and sister-in-law of suspected bomber Hamdi Issac, who is being held in Rome.