A Labour MP has accused the government of complacency and putting the public “at greater risk” by changing the way some terror suspects are monitored.
Pat McFadden’s comments come as police continue to search for Ibrahim Magag, believed to have absconded from his TPim control measure on Boxing Day.
TPims replaced control orders in January 2012.
But the Home Office said Mr Magag’s disappearance had “nothing to do” with the switch.
Ibrahim Magag was last seen in north London on Boxing Day
Detectives appealed for help on Monday in finding Mr Magag, who failed to meet his overnight residence condition on Boxing Day.
The 28-year-old, of Somali origin, was last seen in the Camden area at 17:20 GMT on that day.
TPims – or Terrorism Prevention and Investigation Measures – restrict the movements of people thought to pose a risk to the public, but who cannot be tried for reasons of national security or deported.
Those subject to them can be restricted in areas such as where they stay, who they contact, and where they travel.
Mr McFadden described TPims as “watered-down control orders” which grant “more freedoms” to terror suspects.
He told the BBC Radio Four’s World at One: “I think what they have done is complacent and dangerous and I warned the home secretary and the prime minster about this when the legislation was going through.
“What they have done is put the public at greater risk… and put needless extra pressure on the security services who are charged with monitoring these suspects and trying to keep them under surveillance.”
Mr McFadden said Mr Magag had moved back to London under his TPim when previously he was banned from the city under his control order. TPim notices do not forcibly relocate people, when control orders could.
He added: “The government chose to disarm itself from the powers to relocate suspects… he [Magag] has used his new-found government-given freedom to come back to London and has now absconded.”
A spokesperson for the Home Office said Magag’s disappearance was “the first time somebody subject to a TPim has absconded”.
They added: “In the six years of control orders, there were seven absconds, and in six of those cases the individual was never found in the UK.
“The TPim regime provides effective powers for dealing with those who are engaged in terrorism-related activity but who we cannot yet prosecute or deport.
“By providing extra funding to the security services and Metropolitan Police we are maximising the opportunities to put these individuals on trial in open court.”
David Anderson QC, the independent reviewer of terrorism legislation, told the BBC he agreed the replacement measures were “watered down”, but nevertheless were “still pretty oppressive”.
He added that the end of relocation powers had been balanced by increased resources for surveillance, and TPims were limited to two years as opposed to the indefinite length of control orders.
The identity of people under TPims are usually kept secret, but an anonymity order imposed on Mr Magag was lifted following a request by the police.
Ministers say they do not believe his disappearance is linked to any terrorism planning in the UK, and his TPim was intended to prevent fundraising and overseas travel.