The North's attorney general has received qualified support for his call for an end to prosecutions arising from the Troubles. John Larkin QC was roundly criticised last week by the main unionist parties and victims groups for the suggestion, while the Irish and British governments also distanced themselves from his highly contentious proposal.

Mr Larkin said the potential for achieving justice in criminal cases arising before the Belfast Agreement of 1998 diminished with the passage of time. More than 3,000 murders remain unsolved. He said it was time to draw a line under such cases.

The Catholic Auxiliary Bishop of Down and Connor, Donal McKeown, and the first chairman of the Policing Board, Prof Sir Desmond Rea, have given backing to the idea.

Dr McKeown said the Larkin proposal "is worth considering" and he praised the attorney general for asking "a useful question". He also lauded him for making the suggestion as former US special envoy Richard Haass prepares to return to Belfast to begin intensive negotiations aimed at securing an agreed approach to dealing with the legacy of the Troubles.

“The only route we’ve gone down at present is the judicial route, trials and tribunals, inquests, and that really is not going to be the best way to enable us to get to the truth about so many deaths that have so far been unresolved,” the bishop said. “I think we all are focused not just on drawing a line under the past, but on finding a better way to get to the truth that will enable troubled hearts to be at peace.”

He added: “I think what John Larkin has done for us has actually raised the question – how can we get the best possible deal in the very imperfect circumstances that we have, where many people will never tell the truth about the past, because of embarrassment, because of their own inability to cope with what they’ve done themselves?”

Sir Desmond said: "People have given John Larkin a tough time in the last week to 10 days but he has faced up to the issue and I commend him fully for that." He believed "there is more support in society" for Mr Larkin's ideas.

He insisted he had the strongest sympathies for relatives of those killed during the Troubles and for those who were “injured and who are suffering their injuries to this day. I am not about to criticise anybody in terms of their views in respect of this.”