Belfast priest Fr Des Wilson, who acted as a mediator between rival Republican factions as well as between republicans and loyalists during the Troubles, died aged 94 on Tuesday.
Fr Wilson is credited with having played a key role in Northern Ireland and the west Belfast community for decades.
Relatives for Justice, a support group for relatives of people bereaved, injured or affected by the Troubles, said it was “bereft” following his death.
“He was always on the side of the marginalised, the silenced and the oppressed,” it said. “His support for the families we work with was unwavering. We are diminished without him but remain all the better for having had him.”
Former Sinn Féin president Gerry Adams said there "would be no peace process" without the work of Fr Wilson and Fr Alex Reid, who was also involved in reaching out to unionists.
“The two priests also embarked on an outreach programme,” he said. “They spoke to unionist paramilitaries and facilitated meetings between republicans and loyalists.
“They met officials from the British and Irish governments, and indeed anyone who would listen to them, in the hope that through dialogue they could assist the work of peace building. They pioneered this work.
“They never gave up despite setbacks and serial refusals to talk by the great and the good. Without Fr Des and Fr Alex there would be no peace process.”