The Government has warned republicans who received official letters assuring them they were not being hunted by police that they can no longer rely on them.
Northern Ireland Secretary Theresa Villiers said the Government was not prepared to stand over the factual accuracy of the documents any more, after numerous errors were flagged up in a judge-led review of the so-called on-the-run (OTR) scheme.
But she told a Westminster committee that there were no plans to introduce legislation to change the status of the letters, insisting the most appropriate way of making clear they were no longer of value was with a public statement.
Ms Villiers outlined her intention to the Northern Ireland Affairs Committee but said she intended to make a more detailed statement to Parliament within days.
She said recipients should not rely on the letters.
"If they drew some comfort from those letters in the past they should no longer draw comfort from them in the future," she said.
The issue was thrust into public prominence in February when the case against a man accused of murdering four soldiers in the IRA's Hyde Park bombing collapsed because it emerged he had been sent one of the letters in error, when in fact police were seeking him.
The Old Bailey trial judge found that John Downey's arrest in the UK last year, when he had been told he was free to return, represented an abuse of process - not that the letter conferred immunity from prosecution.
Downey, 62, from Co Donegal, denied involvement in the 1982 attack.
In July, the judge-led review of the scheme, which was agreed between Sinn Fein and the last Labour administration, found that it was systematically flawed in operation but not unlawful in principle.
Lady Justice Hallett said a "catastrophic" error had been made in the Downey case but she insisted the letters of assurance did not amount to amnesties or get-out-of-jail-free cards.
Under the scheme, which started running in 2000, almost 190 republicans who had left the UK jurisdiction received assurances they were not being sought by British authorities.
A number who applied for assurances were not granted them because they were considered as wanted.
Lady Justice Hallett flagged up two other letters where errors had been made.
Police in Northern Ireland have insisted those mistakes have been managed.
The judge also noted that a number of generic letters issued did not include a caveat that prosecutions could be mounted in the future if further evidence emerged.
In the wake of the review's publication, Stormont First Minister Peter Robinson, who in the spring threatened to resign over the controversy, said it was vital the Government acted to withdraw any aspect of the scheme that could potentially prevent others being arrested, or lead to further abuse of process applications in the courts.
Ms Villiers said her statement would not 100% guarantee that abuse of process bids could not be made in the future, but she said the Government was doing as much as it could to avoid a repeat of the Downey case.
She also reiterated the Government's position that it would not be naming any of the as yet unidentified individuals who received the letters, explaining that ministers had obligations under law not to compromise anyone's security and adding that revealing identities also could jeopardise potential future prosecutions.
The Northern Ireland Secretary has consistently insisted the letters never amounted to amnesties and were only factual statements about an individual's status in regard to the authorities at a particular point in time.
But she said the Government was no longer willing to stand over those factual statements, given the errors highlighted in the Hallett report.
Ms Villiers repeated her assertion that any sense of a general "rescinding" of the letters was not applicable.
"I'm not sure rescind is the appropriate term but they should not be relied on," she told MPs.
Ms Villiers had pledged to take legal advice in the wake of the Hallett report to deal with any of the specific issues flagged up by the judge.
She told MPs today that individuals with letters would be treated by the authorities in exactly the same way as individuals who did not have one.
"The Hallett report concludes that errors of fact were made, and errors of judgment may have been made, in cases considered under the scheme," she said.
"The serious systemic failures in the way the scheme was run which are highlighted in the Hallett Report must mean that there is a very real possibility that mistakes were made in other cases which have yet to come to light.
"In the light of this, no-one should take any comfort from these letters.
"No-one should rely on them.
"Decisions of the independent police and prosecuting authorities on whether individuals are prosecuted will be on the basis of decisions made now, not decisions made at some point in the past.
"And those decisions will be made on the basis of all the available evidence.
"To all those who have a letter I say - if the police or prosecuting authorities have evidence which is available today or becomes available in the future to pursue you, they can and will pursue you."
Ms Villiers said her statement to Parliament would detail her decision and "the reasons for it and set out next steps".
"I would urge anyone affected by the administrative scheme to read that statement when it is published," she said.
Asked by Democratic Unionist MP Ian Paisley if the letters were now "useless", Ms Villiers responded: "I don't think they do have any value any more."
The OTR scheme saw names of individuals passed to the Government, the majority through Sinn Fein.
The names were then handed to police and prosecutors to assess their status.
A report on each individual was sent back to the Government and, if they were declared as not being wanted, a letter of assurance was then issued to the individuals.
Police in Northern Ireland were widely blamed for the error in the Downey case for not flagging up his wanted status in their report sent to the Northern Ireland Office (NIO).
Household Cavalry Lieutenant Anthony "Denis" Daly, 23, died in the explosion in Hyde Park on July 20 1982 alongside Trooper Simon Tipper, 19, Lance Corporal Jeffrey Young, 19, and 36-year-old Squadron Quartermaster Corporal Roy Bright.
Ms Villiers repeated the Government's apology over that case to the committee, which is conducting its own inquiry into the controversy.
"The hurt caused by the collective failure in the Downey case is very deep and I would like to reiterate the apology the Government has made for the pain this has caused for victims," she said.
"I would also repeat that while I might not agree with every decision made by previous administrations on the OTR issue, whatever differences of emphasis and approach we might have, I recognise that my predecessors were dealing with very difficult judgments in very difficult circumstances, and that they were at all times acting with sincerity in seeking to move the peace process forward.
"As both the Hallett report and the Downey judgment confirm, this scheme did not grant any amnesty from prosecution.
"No-one was given a 'get out of jail free card'.
"This Government believes in the rule of law and that applies across the board to everyone, including those in possession of letters issued under this scheme."