Northern Ireland's biggest ever roads project appears dead in the water – with the taxpayer left to pick up the near £60m bill.
Regional Development Minister Danny Kennedy confirmed on Monday he would not appeal a court ruling quashing the A5 scheme.
His decision means that tens of millions of pounds already spent on the controversial upgrade will now go to waste.
The bill includes £48m spent on consultants' fees alone.
Last week a High Court judge quashed the decision to press ahead with the £330m dualling of the A5, which runs from Londonderry to Aughnacloy.
The scheme, the largest of its kind in Northern Ireland, formed part of a proposed key cross-border business route linking Dublin and the north west.
But it will not proceed after Mr Kennedy confirmed he wouldn't appeal the court's decision.
"I have considered the very complex legal and procedural matters at length upon receiving detailed legal advice," he said. "It is my intention to accept the ruling of Mr Justice Stephens and therefore I have decided not to appeal."
The group which brought the legal challenge, the Alternative A5 Alliance, said the project was now dead.
But speaking to the Belfast Telegraph, Mr Kennedy refused to accept it was over, adding that a "comprehensive assessment" would now be carried out into the Habitats Directive.
The failure to properly assess the impact on two salmon rivers under the directive led to the court's decision.
"When that is completed we will consider the matter further," Mr Kennedy said.
"I am not able to predict or make wide, sweeping statements about this or any other scheme.
"I am not in a position to predict what is going to happen."
Mr Kennedy's decision could mean the A5 funding is diverted to other projects almost ready to go. An upgrade of the A6 between Belfast and Derry is thought to top his agenda.
But it means £57.6m already spent on the A5 will be wasted.
A breakdown obtained by this newspaper shows £48m has been spent on consultants, £5.2m on surveys and £2.6m on construction. Mr Kennedy said the size of the project meant there were always going to be huge costs.
"This was the largest public scheme ever advanced in Northern Ireland," he added.
"Clearly a scheme of this size will involve significant costs."
The A5 upgrade was given the go-ahead in 2007, with the Republic's government contributing £400m to the cost.
But it was dogged by problems from the outset, with Dublin reducing its initial financial commitment because of the economic situation south of the border.
It was decided to proceed with two sections from Newbuildings to north of Strabane and from south of Omagh to Ballygawley.
After Mr Kennedy gave the scheme the go-ahead last summer, farmers, businesspeople and landowners joined together as the Alternative A5 Alliance.
They mounted a legal challenge and last Monday the court quashed the project.
DUP MLA Jimmy Spratt, who chairs the regional development committee, called for answers as to why the project stalled.
"Many will question why there was a flaw in the original application process and will rightly expect officials to be held accountable for this failure," he said.
"Landowners are understandably angry that they have had no access to their land since September 11, 2012 but, in many cases, are yet to receive any compensation or indeed any indication of the level of compensation."
West Tyrone MLA Declan McAleer, who sits on the regional development committee, said not appealing the A5 ruling would be a costly mistake.
"The fact that despite millions of pounds being paid to consultants on this project, there was a gross lack of oversight by the Department for Regional Development, who should have identified the issues raised in the court judgement, is an indictment of the minister," he said. "The DRD must pursue in earnest a resolution that would be acceptable in order to see that this roads project goes ahead."
SDLP MLA Mark H Durkan called on Mr Kennedy to allocate A5 money to the upgrade of the A6 Derry to Belfast route.
Earlier this month Finance Minister Sammy Wilson said it was time for the Executive to cut its losses on the A5 and focus on the A6.
Brakes are applied to scheme that hit many a pothole
It was years in the planning and has already cost millions of pounds. But after a series of roadblocks and U-turns, Danny Kennedy has put a halt on the A5 upgrade, seemingly for good.
His decision not to appeal a court ruling which quashed the controversial project signals the end of the road – literally.
There have been numerous twists and turns since the Executive agreed to proceed with the scheme in July 2007. The initial plan was for an 88km dual carriageway running between Aughnacloy and Londonderry. The Irish government pledged £400m towards the project as part of the St Andrews Agreement. Part of that was earmarked for the A8 between Newtownabbey and Larne.
In July 2009 the preferred corridor for the new A5 was announced, with costs estimated at £650m to £850m.
But the scheme was dogged by controversy from the start.
Opponents warned the road would rip the heart out of the countryside while farmers voiced concerns about the impact on their livelihoods.
In 2010 Deputy First Minister Martin McGuinness told the Assembly that the Irish government had made a payment of €9m (£7.5m) towards the scheme and remained committed to it.
Referring to the mounting opposition, he insisted that no one should be in doubt that the A5 and A8 would go ahead.
A series of public inquiries were held the following year with Mr McGuinness saying the scheme was now "unstoppable".
But the brakes were put on the project in November 2011 when the recession-hit Irish government withdrew its £400m.
It was decided to proceed with two sections, Derry to Strabane and Omagh to Ballygawley – postponing the final section to Aughnacloy indefinitely.
In July the Department for Regional Development published a report recommending that the entire stretch from Newbuildings to Ballygawley be upgraded.
Regional Development Minister Kennedy announced work would begin in the autumn.
However, in September the Alternative A5 Alliance launched legal proceedings to have the project stopped.
Last month a High Court judge said he was minded to quash Mr Kennedy's decision to proceed. Mr Justice Stephens said the potential impact on two of Northern Ireland's finest salmon rivers had been overlooked.
The decision was confirmed last Monday, but the judge granted DRD a seven-day stay in order to lodge any appeal.
On Monday Mr Kennedy confirmed he had decided not to appeal the ruling.
Opponents celebrate... and hit out at waste
The man who helped slam the brakes on the £330m A5 project has branded the scheme a waste of money.
John Dunbar, who chairs the Alternative A5 Alliance, said there was a feeling of relief and satisfaction in the wake of Monday's announcement by Danny Kennedy.
The group, which includes farmers, businesspeople and landowners, brought a successful legal challenge after the Regional Development Minister gave the go-ahead for the upgrade last year. It has now emerged nearly £58m has been spent on the A5 project to date.
"This has been a total and absolute waste of taxpayers' money," said Mr Dunbar. "There was never a proper consultation process with the community – it was more like a dictation of what was going to happen."
Mr Dunbar said funding should now be made available for improvements to the existing road, rather than building a new carriageway which wasn't needed.
He added: "That is why we are called the Alternative A5 Alliance – consideration was never given to an alternative."
Another member, Laura Kwasniewska, said opponents of the road were delighted that "common sense has prevailed ".
"They have lived with the threat posed by the new road scheme for the past four and-a-half years and it has taken its toll on the health of many individuals," she said. Ms Kwasniewska said delight was tinged with "an understandable degree of outrage".
Belfast to Derry route could benefit
An upgrade of the road between Belfast and Londonderry could be fast-tracked after a legal challenge left plans for the A5 in disarray.
Of the £330m allocated by the Executive to the development, £100m was set to be spent in this financial year.
Regional Development Minister Danny Kennedy said he now hoped to work with Executive colleagues to ensure that money was diverted to other projects that are almost ready to go.
These include the widening of the Knock dual carriageway in Belfast and a bypass around Magherafelt.
But it is understood that the A6 project is at the top of the minister's wish-list. The plan incorporates the construction of two separate sections of dual carriageway – between Derry and Dungiven and between Castledawson and Randalstown.
If it was given the green light, a tendering process would have to be entered into before work could get under way in potentially nine to 12 months' time.
Money could also be diverted to enhance maintenance work on parts of Northern Ireland's existing road network.