The Ulster Unionist leader, Mr David Trimble, has appealed to the nationalist Garvaghy Road residents in Portadown not to oppose the Drumcree Orange parade "by physical means".
His call, in a letter to the Residents" Coalition, comes as tension mounts about next Sunday's Drumcree march. Yesterday the Parades Commission announced that it would not permit the Orange parade to march on Garvaghy Road. Last night a High Court challenge to the decision was being considered by the Orange Order.
The RUC Chief Constable, Mr Ronnie Flanagan, declined to comment. His force faces enormous public order problems if the Orange marchers defy the ruling and try to force their way along the contested route.
Last week Mr Flanagan said the Parades Commission had "the lawful responsibility to make decisions in respect of contentious parades. I am absolutely determined that their decisions will be enforced on the ground."
The Northern Secretary, who would not comment on the decision because she may be asked by Mr Flanagan to overturn it on the grounds of public order, said it was "regrettable" that the Parades Commission had to make a decision. Dr Mowlam said residents and Orangemen had five days to talk and reach an accommodation and prevent violence.
Mr Trimble's letter to the Garvaghy Residents' Coalition said the people of Northern Ireland had voted overwhelmingly for peace and they now "quite rightly" expected it to be delivered.
"That now requires you to indicate that you will not oppose by physical means the return to central Portadown of the local Orangemen by the Garvaghy Road after their church service at Drumcree Church," he said.
Acknowledging the residents might describe this as distasteful, Mr Trimble said making peace "has required many of us to accept things which are distasteful, such as the early release of convicted prisoners".
The rerouteing of the Drumcree march away from the Garvaghy Road was announced in Belfast by the Parades Commission chairman, Mr Alistair Graham. This decision may be subject to challenge by the Orange Order this week in the High Court in Belfast, which is considering its options.
"Given the absence of any positive move towards accommodation," Mr Graham said, "we cannot see at this stage how a parade could proceed again this year without having a very serious impact on community relationships, both locally and more widely across Northern Ireland."
The Garvaghy residents group welcomed the move but said it was "painfully mindful" of the events of 1996 and the inability of the RUC to enforce a legally-binding re-routing decision at the time.
"We would urge nationalists to exercise extreme vigilance over the coming days, and we would appeal to unionist leaders to urge restraint and compliance with the commission's ruling," it said.
The Grand Orange Lodge of Ireland, said the "decision should be condemned by all those who value civil rights."
Mr David Jones, spokesman for Portadown Orangemen said: "We don't recognise the Parades Commission decision and it will be our intention to parade - as we have done since 1807 - to Drumcree parish church, hold our service and return back into Portadown along the Garvaghy Road." If the police stopped them, he said, they would "go as far as we can and then stage a protest".
Ms Brid Rodgers, an SDLP Assembly-member for the area said the commission ruling was "sensible, correct and in accordance with their own guidelines as set out in the legislation". She appealed to the Orange Order to engage directly with the residents.
The Democratic Unionist Party leader, the Rev Ian Paisley said he had told the British Prime Minister, Mr Blair, that the right of the Orangemen to march the traditional route must be upheld.
A local Sinn Fein Assembly member, Ms Dara O'Hagan, said the decision would give a breathing-space to residents but would be viewed with scepticism.