The Parades Commission has announced that a planned Orange Order parade is to be allowed on the mainly-nationalist Garvaghy Road in Portadown.
The commission said the parade on Sunday should start earlier than the Orange Order wanted and with fewer people - but can go ahead.
The decision is facing a legal challenge from the Garvaghy Road Residents' Coalition which opposes the march and has said the challenge will be heard on Saturday morning.
Rather than start at 13:00 BST on Sunday as intended, the commission has said the march can begin at 08:00 and with 35 participants rather than the 60 the Orange Order requested.
In a detailed document known as a determination, which was published on its website, external, the commission said: "This decision is not, and should not be perceived, as a victory for one side or a loss for another.
"It is the outworking of the application of the legal framework to the facts available to the commission."
The five-person commission, led by Prof Evelyn Collins, held face-to-face talks with the Orange Order earlier this week, and held a separate meeting with the Garvaghy Road Residents' Coalition.
Senior police officers were also consulted about the planned parade.
The Police Service of Northern Ireland (PSNI) said it had activated "mutual aid arrangements to support contingency planning for a policing operation" in Portadown on Sunday.
It is understood about 200 officers are coming from Scotland.
Within the 31-paragraph determination by the Parades Commission, details were revealed of conversations held with the PSNI.
The document stated: "The police made both written and oral submissions, indicating that they, at the time of making them, had no information indicating that the parade would result in disorder or violence."
It said the PSNI were "planning for all reasonably likely scenarios, both known and unknown".
The Residents on the Garvaghy Road said they are ''furious'' over the decision to grant permission for the parade, adding the community were "fearful about what will happen over the weekend".
"The feelings of people in the local community here, you can describe them as shock, and you can also describe them as anger," said Breandán Mac Cionnaith of the Garvaghy Road Residents' Coalition.
"After 28 years of this community being able to avoid confrontation, the parades commission by their decision is creating the grounds for a confrontation."
The residents' coalition are applying to the High Court in Belfast to overturn the decision.
A group, including Sinn Féin representatives, gathered outside the court to support the Garvaghy Road Residents.
The Parades Commission has been in the political spotlight since its previous Drumcree determination was quashed in the High Court in August.
A review of the commission has since been ordered by the Northern Ireland Office.
The Drumcree parade dispute began in the mid-1990s and it almost derailed the peace process at the time.
Violence related to the dispute resulted in riots, roadblocks and murders.
When the Orange Order was prevented by police from walking down the route in July 1995 there was a tense stand-off. It was the same for the next three years.
The Parades Commission began operating in 1998 to regulate parades and try to defuse tension around marches.
Its decision not to allow a march down the Garvaghy Road that summer has been challenged by the order over the past three decades.
The Prime Minister Andy Burnham has appealed for calm.
Speaking to BBC News NI, he said it was a matter that had been "independently determined" and that it was not for him to cut across the commission.
Asked about the potential effect on community relations, he replied: "I appreciate it's easy for me to to say that from where I'm sitting, and I know there'll be strong feelings in Northern Ireland, and I know the first minister has concerns."
Secretary of State for Northern Ireland Chris Bryant said: "Hard-won progress has withstood many moments of sharp disagreement over the years. It must do so again. We have come too far."
First Minister Michelle O'Neill, who was amongst the gathering at the High Court earlier, described the decision as having "no reasonable or logical basis".
In a statement, the Sinn Féin vice president said the march was "steeped in a history of hate, sectarian violence, and murder", adding that people were "absolutely dismayed" by the announcement.
The Deputy First Minister, Emma Little-Pengelly said she was "appalled" to see what she describes as "those who have decided to ramp up tensions, and dial up the rhetoric".
"Michelle O'Neill should be dialling down the temperature, not giving stump speeches," she said on X.
"The Portadown Orangemen have made clear there is absolutely no threat nor violence. There is nothing to fear from them and absolutely nothing to be apprehensive about," she said on X.
The Sinn Féin President Mary-Lou McDonald, who was amongst the gathering at the High Court earlier said the decision was "utterly reckless" adding that it shows a "complete disregard" for the rights of the community of the Garvaghy road.
"This is a grave situation, recklessness of this scale of course has implications and consequences."
She called for anyone that can intervene, including the prime minister and taoiseach, to "put this right".
The leader of the Democratic Unionist Party (DUP) Gavin Robinson called it a "significant and long-overdue breakthrough", but said the "severe restrictions" would require "careful consideration".
"We are in 2026 and Orangemen walking silently and peacefully down a road should not be a major issue in a shared society," he added.
The Ulster Unionist Party (UUP) leader Jon Burrows said it was a "significant determination" adding that he has "every confidence" the parade will "conduct itself lawfully and with dignity".
"Whatever the outcome, everyone in every community must respond peacefully and lawfully... We need calm heads and measured words."
The leader of the Traditional Unionist Voice (TUV) leader Jim Allister welcomed the decision but called the imposed conditions "churlish".
"I trust those who exposed their own intolerance in trying every trick to frustrate this parade will now accept the rule of law. That is the test for them," he said.
Stand by for 48 hours of frenetic political, legal and security activity before the planned Drumcree parade on Sunday afternoon.
Every effort will be made by nationalist residents on the Garvaghy Road in Portadown to overturn the decision to give the march the go-ahead.
The Orange Order leadership in Portadown may decide to keep a low-profile, reluctant to say anything that could jeopardise the scheduled parade.
At the same time, the police in Northern Ireland will be planning a detailed security operation for the parade, until told otherwise.
For all concerned, it is going to be an intense weekend.
