Construction work on the new €1.7bn national children's hospital has stalled indefinitely amid a dispute over who should pay for the extra costs of reopening the site.
No work has been carried out on the controversial project, which has been beset by delays and budget overruns, at St James's Hospital in Dublin since the Covid-19 lockdown at the end of March.
Building work stopped on March 31 - but despite restrictions on the construction sector easing on May 18, work has yet to restart on the site.
The National Paediatric Hospital Development Board (NPHDB) confirmed there is a dispute with the developer Bam over who should bear the extra costs of the site being closed for over three months and reopening it while complying with social-distancing rules, which will mean fewer workers on site.
This is likely to further delay the completion of the hospital, which is due to open in 2023.
The NPHDB argues that construction can continue while the dispute is being resolved. Bam declined to comment.
"There is no timeline for when it will be back up and running. Discussions are ongoing," a source said.
The delays were described as "extremely concerning" by Fianna Fail TD James Lawless who confirmed the indefinite delay through a parliamentary question to Health Minister Stephen Donnelly.
The NPHDB said in a statement: "The NPHDB has been engaging with Bam to ensure the earliest possible reopening of the site.
"Some matters remain unresolved, relating primarily to the cost implications of the closure and reopening of the site and who should bear them.
"This should not prevent Bam from returning to the site, however, as these matters can be resolved through the agreed dispute management process while work on site continues, and for that reason the NPHDB has been clear on its expectation that the main contractor meets its obligation by returning to the site without further delay."
The new hospital is scheduled to be completed by the end of 2022 and handed over to Children's Health Ireland to open in 2023.
However, the project has been beset by delays and the NPHDB said Bam had failed to make up for time lost.
"There will be delays associated with the requirement to cease works on the site due to Covid-19 restrictions and following reopening in respecting social distancing," it said. "However it is too early to fully assess the time or cost impact of the pandemic."
Mr Lawless said he has now written to Mr Donnelly outlining his concerns and seeking further clarity on when work will restart on the site.
"This project has already undergone numerous delays and expenses. Neither it nor the State can afford more controversy and delay now," he told the Herald.
"What is so special about this particular site that sees tools still downed almost two months after every other builder is back at work?"