Briefing notes prepared for former British prime minister Margaret Thatcher and northern secretary Tom King in the wake of IRA murders of two RUC officers, encouraged the politicians to play down speculation of Garda collusion with terrorists.
The briefing compiled within hours of the 1989 killings of chief supt Harry Breen and supt Bob Buchanan also encouraged the then prime minister and the secretary of state to set the killings in the context of the wider sectarian murders which were happening that year.
This was because "the impression should not be given that we are only really concerned about murders of the British security services", the notes explained.
The briefing notes, which were produced at the Smithwick Tribunal this morning, also suggested the politicians publicly welcome the co-operation of the Irish Government.
The documents were prepared in the immediate aftermath of the IRA killings in a "question and answer" format for the politicians to use in anticipation of the issue being raised in the House of Commons.
Mr Breen and Mr Buchanan were killed in an IRA ambush in south Armagh within minutes of leaving a meeting in Dundalk in March 1989. Their deaths gave rise to immediate speculation on both sides of the Border as to the presence of an IRA mole among the Garda in Dundalk.
But the briefing notes cautioned that questions of this nature should be met with the answer that speculation "plays the terrorists' game".
The material stressed there was "no shred of evidence to support these allegations which are extremely dangerous". The prime minister particularly was urged not to "add fuel to the fire" by encouraging such speculation.
The tribunal also heard two members of the assassination squad which ambushed the RUC men were well-known Dundalk republican Patrick 'Mooch' Blair and a man identified as Hard 'Bab' Hardy.
