The IRA did not want Sinn Fein involved in proposed back channel talks with the British about ending the Troubles.
The message from a senior Irish official to colleagues in the Department of Foreign Affairs (DFA) has been newly-released by the National Archives under the 30-year rule.
The IRA s Army Council told two prison chaplains in the spring of 1990 that it was prepared to enter exploratory talks with the UK, according to the internal Irish government communique.
The two chaplains at the Maze prison near Lisburn, Rev Will Murphy and Fr John Murphy, had been trying to encourage prisoners from both sides to move away from violence.