The coalition government is to create a commission to review the Human Rights Act following a successful bid by two terror suspects to avoid deportation.
Abid Naseer and Ahmad Faraz Khan, both 23, had argued that they would face torture or death in Pakistan.
The Act is a source of a policy divide between the Conservatives and Lib Dems.
The Lib Dems are opposed to attempts to dilute it, while the Tories had proposed replacing it with a "British Bill of Rights".
Attack
The Human Rights Act 1988 incorporated fundamental rights enshrined in the European Convention of Human Rights into UK law.
These included the right to life, the right to family, freedom from torture and the right to a fair trial.
The two men were among 10 Pakistanis arrested last April as part of a massive counter-terrorism operation in Liverpool and Manchester.
The security services believed the men were planning to attack within days of their arrest, but neither was charged.
However, the Special Immigration Appeals Commission (Siac) said it believed Mr Naseer was an al-Qaeda operative.
The Home Secretary, Theresa May, said she would not be appealing against the ruling handed down by Siac but she was disappointed.
She said: "As the court agreed, they are a security risk to the UK. We are now taking all possible measures to ensure they do not engage in terrorist activity."
Altogether five men – who had been tracked by MI5 before the raids last year – were appealing against deportation.
Much of the detail in the case was presented to Siac – a court which deals with such cases – in secret during the past three weeks.
Abdul Wahab Khan, 27, and Tariq Ur Rehman, 38, who were also arrested at the time, lost their deportation appeals.
They had already returned to Pakistan.
Mr Justice Mitting said they were committed Islamists who knew of Mr Naseer’s plan.
Mr Ur Rehman denied this and told the BBC: "I have no link with al-Qaeda; I am not an Islamic extremist. I am a normal Muslim – I go to the mosque and pray."
Student Shoaib Khan, however, won his appeal, with the court saying there was no evidence of wrongdoing against him.
His lawyer Amjad Malik told the BBC that his 31-year-old client, who is also currently in Pakistan, wanted to return to the UK to resume his studies.
Al-Qaeda operative
In his judgement, the judge said Mr Naseer was sending e-mails to a contact in Pakistan – and that the recipient was an "al-Qaeda operative".
The e-mails were said to be at the heart of the plot and culminated in a message sent to Pakistan in April 2009 in which Mr Naseer said he had set a date to marry, something MI5 said was code for an attack date.
"We are satisfied that Naseer was an al-Qaeda operative who posed and still poses a serious threat to the national security of the United Kingdom," the judgement said.
It added: "Subject to the issue of safety on return, it is conducive to the public good that he should be deported."
The judge said Ahmad Faraz Khan had become a "knowing party" to the plan because he had "undergone a radical change in view" between leaving home and studying in the UK.
But in both cases, Mr Justice Mitting said it was impossible to return the men to Pakistan.
"There is a long and well-documented history of disappearances, illegal detention and of the torture and ill-treatment of those detained, usually to produce information, a confession or compliance," said the judgement.
Control order
Following the court’s decision, the government’s independent reviewer of terrorism legislation, the Liberal Democrat peer Lord Carlile, said he hoped it would look at ways of ensuring people would be treated properly if they were returned to their native countries.
The BBC’s home affairs editor, Mark Easton, also said it was likely that a control order would be used to restrict the movement and activities of the two men and to keep them under constant watch, although ministers would be unable to confirm this.
However, he said this was also an issue of contention between the two parties.
The Lib Dems have described the orders as "an affront to British justice" while the Conservatives have said a review is needed.
In all, 11 men were detained after police raided a series of locations across Liverpool, Manchester and Lancashire in April 2009.
Ten of them were from Pakistan, who were all either close friends or loosely known to each other.
At the time officials feared an imminent attack.
But no explosives were found and all of the men were released without charge after two weeks.
They were immediately detained again under immigration laws after the then home secretary sought their deportation, saying they were still a threat to national security.
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