An IRA prison escapee pardoned by Margaret Thatcher's government has said she was a pragmatist whose ministers made small concessions as part of dealings with Ireland.
Donal Donnelly, 74, fled Belfast's Crumlin Road jail - which he dubbed Europe's Alcatraz - on Boxing Day 1960 while serving a sentence for membership of the armed group during its 1950s border campaign.
Former Northern Ireland secretary Lord Hurd, part of a Conservative government scarred by republican violence including the Brighton bombing just months earlier, agreed to grant the Royal Prerogative of Mercy (RPM) in May 1985.
The decision was made less than two years after the biggest prison break-out in UK history by 38 republicans and came as Lord Hurd began talks with the Irish Government ahead of the Prime Minister's landmark deal on cooperation with the Republic.
Donnelly said: "People would probably be surprised that she was at it but she was a very pragmatic woman."
He speculated the decision to grant the concession was likely to have served some final purpose.
"They knew that I was not involved with the Provisional or the Official IRA; effectively I was no threat to them," he said.
Donnelly was born in Omagh in Co Tyrone and now lives in Dublin.
He was serving a 10-year sentence when he escaped in 1960, using hacksaw blades, torn sheets and electric flex as makeshift tools.
Afterwards he lived openly in the Republic, working as a planning and procurement manager at a multinational firm, and published a book on his flight from prison - Escape From Crumlin Road, Europe's Alcatraz.
Official files released by the Public Records Office of Northern Ireland (PRONI) reveal Donnelly petitioned three times for the remainder of his sentence to be remitted, to allow him to work for his company in Great Britain and Northern Ireland. He said he was initially rejected.
He said: "The British government was probably saying yes to what I would consider small things to indicate that they were not as intransigent."
He added: "Sending out a message that they were not pleased was saying no to what we would consider as unimportant things and another time they might say yes."
The use of pardons following the 1998 Good Friday peace agreement was disclosed earlier this year after the dramatic collapse of the trial of a man accused of the Hyde Park bombing.
Records released on Friday shed light on the thinking of senior civil servants considering the controversial practice much earlier, while the conflict was still fierce and when Lady Thatcher's government was adamantly opposed to granting any concessions to republicans.
The month Lord Hurd approved the pardon he was tasked with overseeing talks with the Irish Government on the Northern Ireland issue, which led to the Anglo-Irish Agreement (AIA) - for the first time giving the Republic a consultative role on Northern Ireland and leading to closer security cooperation.
Less than a year earlier, in October 1984, the IRA had targeted a Conservative Party conference in Brighton in a bombing which nearly wiped out the cabinet.
Lady Thatcher had become famous for her unbending handling of the republican prison hunger strike of 1981, in which 10 men died including Sinn Fein MP Bobby Sands.
But her signing of the 1985 agreement with Ireland paved the way for the 1998 Good Friday peace accord which ended IRA and loyalist violence and allowed for the release of conflict prisoners.
In the newly-released records an NIO official suggested: "I cannot help feeling that given the Northern Ireland situation, the time will never be exactly right.
"However the prisons are quiescent at the moment, the Maze escape is 18 months behind us and the trial of the recaptured escapers is some months ahead.
"If we hold off until the late summer we may well end up deferring action yet again rather than remit Donnelly's sentences during, or immediately after, that trial."
An extradition agreement between Britain and the Republic was introduced in 1987 and the first extradition happened some years later.
Current Northern Ireland secretary Theresa Villiers has revealed that the royal prerogative was exercised in Northern Ireland on at least 365 occasions between 1979 and 2002.
But the true total may well be higher as the NIO has been unable to find the records for the 10-year period from 1987 to 1997.
A spokeswoman for the department said: "The use of the Royal Prerogative of Mercy has changed significantly since 1985.
"The introduction of the Criminal Cases Review Commission, statutory provisions on sentence remission for assisting offenders, and other routes for cases to be reviewed by the courts, mean that use of the RPM is now far more rare. It has not been used in Northern Ireland since 2002."