A new contractor is being sought for the redevelop Ulster GAA's flagship stadium, Casement Park in Belfast.
The site has been earmarked as a venue for use in the UEFA Euro Championships in 2028 as part of a joint host bid between the UK and Ireland.
In a statement issued on Friday, Ulster GAA said its "long-standing contractor" Heron Bros "will not proceed to deliver the main works contract for new Casement Park".
It added that it's "determined and confident that construction work will commence in line with the timelines required to host the UEFA Euro Championships in 2028".
A spokesperson for Heron Bros said it's "disappointed with the news that Ulster GAA has been left with no choice but to bring the current procurement process for the rebuild of Casement Park to an end due to technical restrictions within the Public Contract Regulations."
Meanwhile a spokesperson for the Department for Communities said "we remain fully committed to the delivery of this flagship project" and is "progressing the options that are available".
The joint bid ran unopposed after Turkey withdrew from the process.
One of the sites included in the joint bid was Belfast's Casement Park. It's due to be turned into a 34,500 capacity ground.
The stadium has been derelict for a decade and discussions around its redevelopment have been long running with many legal challenges.
In September, the Buckingham Group went into administration.
On Friday, Ulster GAA said Heron Bros would not proceed to deliver the project.
In a statement, it said: "Ulster GAA today advises that Heron Bros Limited, our long-standing construction contractor, will not proceed to deliver the main works contract for the new Casement Park.
"We are working closely with our partners in the Department for Communities (DfC) to progress procurement of a contractor using recognised frameworks for major construction projects.
"We are determined and confident that construction work will commence in line with the timelines required to host the UEFA EURO Championships in 2028.
"Ulster GAA is bringing forward critical aspects of the construction programme to progress the project, at pace, during the process to secure a new main contractor in the coming months, including site clearance and a range of enabling works packages.
"Heron Bros Limited participated fully in a recent due diligence exercise following its JV partner, Buckingham Group Contracting Ltd, falling into administration and demonstrated their capacity and capability to bring this project forward.
"It has become clear that the restrictions of the Public Contract Regulations prevent Ulster GAA from pursuing its preferred option of retaining and modifying the existing contract for the project.
"Ulster GAA sincerely thanks Heron Bros Limited for its commitment to this project and its work over the past ten years.
"In particular, we want to highlight the work undertaken with the local community in other connected projects, including the Casement Park Social Club."
Meanwhile, a spokesperson for the Department for Communities told UTV: "I can confirm that we have been informed by UCGAA that the existing Casement Park construction contract cannot be modified in accordance with Public Contract Regulations 2015.
“We are progressing the options that are available via existing procurement frameworks for major construction projects with pre-qualified contractors, providing an effective delivery model for the project going forward.
“We remain fully committed to the delivery of this flagship project, which is uniquely placed to boost the development of both Gaelic games and football, as well as offering long-term economic and social benefits in Northern Ireland and beyond.
“We are continuing to work closely with the UCGAA and all our partners across Government, local Government and the IFA to ensure delivery in line with the UEFA requirements for the hosting of Euro 2028 matches in Northern Ireland.”
A spokesperson for Heron Bros told UTV: “Heron Bros Ltd is disappointed with the news that Ulster GAA has been left with no choice but to bring the current procurement process for the rebuild of Casement Park to an end due to technical restrictions within the Public Contract Regulations.
“We have remained committed to the Casement Park redevelopment project for more than 10 years and will now await details of any future procurement exercise before considering the potential for our company to be involved in any future bid to deliver the important stadium project.”
Beyond questions around whether the redevelopment will be completed by the summer of 2027, in order to be ready for the Euros in 2028, there are also queries over how much the work is going to cost.
Initially the cost was estimated as around £77.5m but some have raised concerns that could more than double.
Where the funding will come from is also highly debated, however the GAA said it is willing to pay at least £15m, with further funding expected to come from Stormont, as well as the British and Irish governments.
Sinn Féin MP for West Belfast, Paul Maskey said finding a solution that gets contractors on the ground and work started to build Casement Park ahead of Euro 2028 must be a top priority.
“It is important that the Irish and British government work with the football associations and the GAA to get this flagship project over the line quickly and on time," he said.
Meanwhile SDLP Councillor for the area, Paul Doherty said the redevelopment of Casement "isn’t only about sport, it’s about improving the local economy, creating jobs and attracting investment and that’s something this area badly needs.”
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