MR John Major has said criticisms of the British government by the Taoiseach and Cardinal Daly "did not advance progress one whit" and "would have been better not made".
In last night's BBC Panorama interview, the Prime Minister was asked about the Taoiseach's charge that Britain had breached the canons of democracy - and Cardinal Daly's assertion that he felt betrayed by the decision to allow the Drumcree march to proceed.
Mr Major said he didn't want toe "traipse over old ground". But he insisted: "If mistakes were made, the mistakes ... were in making those comments." He said the Taoiseach's remarks following their conversation last week were extremely unhelpful.
And while Mr Major contended "that is behind us now", he again asserted the Drumcree decision was an operational one, decided by the RUC chief constable, free of political interference.
Mr Major said "the belief that ministers at some distance can give detailed instructions on how to handle a street order or disorder is fatuous. So the answer is no instructions were given at all."
The Prime Minister confirmed the RUC Chief Constable would attend the Inter Governmental Conference on Thursday to repeat that assurance. "The Chief Constable will be there to tell the Irish, looking into their eyes, that he made the operational decisions and that what they had said was mistaken", he said.
Asked if he hadn't yet convinced the Irish Government, Mr Major replied: "You must ask the Irish Government that. They should know by now that we were not (involved in the decision). If they do not acknowledge that we were not, then I find it hard to understand what could possibly convince them. We were not. Paddy Mayhew has said not, the Chief Constable has said not in the clearest possible terms and they will be told that face to face. I hope they will acknowledge that."
Of the decision itself, Mr Major said: "I think he did make the right decision ... The problem he faced was that neither side, neither the marchers nor the residents, were prepared to reach a compromise to make matters at all easy either for the public at large or for the Chief Constable."
Mr Major rejected the view that the decision was seen as a "victory" for the Orangemen: "It might equally have been claimed as a victory by nationalists when the original march was stopped ... Nobody claimed then that it was a defeat for the unionists, yet now people are saying it is a victory for the unionists. Both these terms - defeat/victory - this is just a further illustration of the intemperate way in which so much of the debate in Northern Ireland is carried out."
Mr Major refused to "lavishly" criticise either side. But when pressed he said: "Both sides were wrong. The Orange Lodge were wrong in seeking to proceed in the way that they did. And I think the Garvaghy Road residents were unreasonable in the way they refused to discuss and to compromise for a long time on how a peaceful march could have been passed through the Garvaghy estate. So there is ample blame on both sides.
Asked if he was dismayed by the actions of unionist leaders at Drumcree, Mr Major said: "It depends what particular actions you have in mind. I was delighted that they urged people to be restrained."
When pressed further, Mr Major said: "Don't invite me to make it more difficult to sit down with those politicians and reach an accommodation."