A challenge to the decision to allow a controversial Orange Order parade to go down a predominantly nationalist road is being heard in court.

The deadlock over the proposed march in Portadown – opposed by residents of the Garvaghy Road – has lasted since last Sunday morning.

The stalemate has reopened what was once the most bitter parading dispute in Northern Ireland, with stand-offs in the mid-to-late 90s accompanied by riots, roadblocks and killings.

The fresh Court of Appeal application argues that the Parades Commission, the organisation that approved the march, had “materially misdirected itself” on the police assessment of the potential for disorder.

The application also said the commission had not given an “accurate representation” of PSNI evidence in its decision.

The Garvaghy Road Residents Coalition (GRRC) and their legal representatives arrived at the court on Monday morning.

Loyalist activist Jamie Bryson, who has been acting as legal advisor to the Orange Order, Democratic Unionist Party (DUP) MP Carla Lockhart and Orange Order legal representatives also arrived.

The hearing began in Belfast at about 10:30 BST.

On Friday 25 September, the Parades Commission decided that the march could go ahead with restrictions in place.

The residents’ appeal will be the latest legal challenge since it was given the go-ahead after three separate legal hearings over the course of 13 hours late on Saturday and into the early hours of Sunday morning.

Last Sunday, the parade, from Drumcree Church into Portadown, did not happen due to a large protest on the mainly nationalist Garvaghy Road.

Protesters have since remained on the road, although in much smaller numbers, and the Portadown District Orange Lodge has maintained a presence at Drumcree Church, about a mile away.

On Tuesday, lawyers for the Garvaghy Road Residents’ Coalition (GRRC) issued a fresh legal bid to try to prevent the march from going ahead.

Northern Ireland Secretary Sir Chris Bryant held talks held talks with both sides last week, which ended without agreement.

PSNI Chief Constable Jon Boutcher also discussed the dispute at a public meeting of the Policing Board in Belfast on Thursday, where he said the policing operation has cost about £3m so far.

A police investigation into anyone suspected of breaking the law in relation to the dispute is ongoing.

Sinn Féin councillor, Catherine Nelson, is among the politicians who have been taking part in protests, which police have described as unnotified and “therefore illegal”.

Speaking ahead of the court challenge on Monday, she said that “legality and morality aren’t always the same thing”.

“Sometimes peaceful civil disobedience, which is what you’re seeing on the Garvaghy Road, is how people challenge an injustice,” she told the BBC’s Good Morning Ulster programme.

Democratic Unionist Party (DUP) assembly member Jonathan Buckley said the Orange Order would abide by Monday’s court ruling and accused Sinn Féin of disrespecting the courts and the rule of law.

He said the Portadown District did not agree with the Parades Commission’s 1998 ruling that the Orange Order should not march down the road – but they had obeyed it “for 28 years”.

Ulster Unionist Party (UUP) leader Jon Burrows told The Nolan Show that a resolution was needed “urgently” and “the people of Northern Ireland need leaders to lead”.

Traditional Unionist Voice (TUV) leader Jim Allister said the Portadown District had “shown themselves more than capable of reaching out to try and resolve” the situation but “every time they do they get a kick in the teeth”.