Many of those involved in the exercise believe the talks, which began in 1990 and are still continuing, played a significant part in convincing republicans to steer towards the IRA ceasefire of August 1994.
During the period involved Sinn Fein policy has been adjusted to take considerably more account of the rights of Protestants and Unionists. Last month a number of speakers at Sinn Fein's annual conference alluded to such contacts and stressed their importance.
The long-running contact has been conducted in conditions of some secrecy, generally taking place in a monastery in the Falls Road district of west Belfast. Among the prime movers were Fr Alex Reid and Fr Gerry Reynolds, two Redemptorist priests based at the monastery, and the Rev Ken Newell, a south Belfast Presbyterian minister.
Today the contacts, which survived the breakdown of the IRA ceasefire in February, involve up to 10 Protestant clergy and lay people. They remain a sensitive issue as many Protestants disapprove of any links with republicans.
Some members of the group, including the two priests, have also for some years been in contact with leading figures in extreme loyalist paramilitary groups. The contacts are described by the Rev Newell in a book to be published this week, The Fight for Peace, and in a Channel 4 "Dispatches" programme to be broadcast on Wednesday.
In an unprecedented tribute to Mr Adams from a Protestant clergyman, Mr Newell said:"There is a side of him that is very reflective and warm, and he deeply believes people should be together and not apart."
The Sinn Fein president attended the talks on a regular basis for several years, before suggesting the circle should be widened to involve other members of Sinn Fein. They now involve figures from the Church of Ireland and the Presbyterian and Methodist churches.
Mr Newell said that in 1992, after 18 months of talks, the Protestants involved came to be convinced that Mr Adams and the other republicans were serious about peace. He described the Sinn Fein president as originally "emotionally distant" but said he developed a growing respect for the Presbyterian and Protestant traditions.
As the talks went on, said Mr Newell, the Protestants concluded that the Sinn Fein members had a new agenda and were genuinely looking for peace.
t Mr Adams said yesterday that Sinn Fein would shortly decide whether or not to take part in the Northern Ireland elections being held on 30 May.
He said in a radio interview: "We all have to be prepared to make the necessary flexible compromises to try and bring about a proper democratic negotiated settlement, which has the agreement of all the people of the island. That has to be the main focus."Reuse content