Human rights groups have expressed fears over the fate of 10 people facing deportation from the UK because they pose a threat to national security.
Mr Clarke says he has the necessary reassurance on torture
The Jordanian cleric Abu Qatada, who is subject to a control order, is among them, the BBC has learned.
Charles Clarke said things had changed since the London bombings. It was vital to act against threats to the UK.
Tories backed Mr Clarke but critics are concerned at deportations to countries with poor human rights records.
The home secretary insists he has the necessary reassurances from Jordan that deportees would not be "subject to torture or ill-treatment".
Shami Chakrabarti, of human rights group Liberty, said it would take "more than a piece of paper to convince me that Jordan and some of these other possible north African and Middle Eastern regimes are suddenly safe".
And Amnesty International's Mike Blakemore said the assurances the government was trying to obtain were not worth the "paper they were written on".
"We are taking the word of known torturers that they won't do this again," he said.
The Muslim Council of Britain said it understood the government had been seeking assurances from some countries "that they will not torture these proposed deportees", but it added "we still have some concerns about their human rights".
Liberal Democrat president Simon Hughes said he would prefer to see the detainees prosecuted in the UK rather than deported to their home countries.
Home Office minister Hazel Blears insisted the government had reached a formal agreement with Jordan and that there was an "independent mechanism" to monitor any deportee's treatment.
Shadow home secretary David Davis said he supported the government's stance, saying: "It is vital that the home secretary is able to use his powers to deport or exclude foreign nationals who threaten our national security."
The Immigration Advisory Service's Keith Best said ministers already had enough powers to deal with terror suspects.
The 10 foreign nationals were detained after raids in Leicestershire, London, Luton and the West Midlands, follow an agreement between the UK and Jordan that deportees would not be persecuted.
Under the Human Rights Act, the UK cannot deport anyone to a country where they may face persecution.
Those detained include Jordanians, Lebanese, Algerians and other north Africans.
The government has been negotiating with 10 countries, including Lebanon, Algeria and Jordan, to gain guarantees any deportees will not be mistreated.
Abu Qatada was one of the so-called Belmarsh detainees, who was detained in the high security jail without charge for around two years.
He has been sentenced in his absence to life in prison by a Jordanian court in relation to a series of explosions there.