The collapse of Carillion has delayed the opening of the new £335m Royal Liverpool Hospital, with bosses saying it is unlikely to be finished in 2018.
The hospital trust's chief executive Aidan Kehoe said opening the 646-bed site in 2018 would be "challenging".
First due to open in March 2017, the project has been repeatedly delayed after asbestos was found on site, while remedial building work was also needed.
Construction giant Carillion collapsed last month with debts of about £1.5bn.
The Insolvency Service and accountancy firm PwC, which is overseeing Carillion's liquidation, declined to comment on the hospital delay.
Liverpool Riverside MP Louise Ellman, who has previously stated the hospital was "around 90% complete", said she would be pressing ministers to minimise the delay because she did not "want months to pass before work resumes".
She also said it was "important that subcontractors who have not been paid are supported, so that they can remain viable and continue their work", adding: "A new contractor must be appointed."
Gail Cartmail, assistant general secretary of the union Unite, said the Royal Liverpool delay had revealed "the stark reality" of what Carillion's collapse meant for communities and the construction industry.
She said: "The Government needs to prioritise how stalled projects are restarted and what other support can be given to protect jobs and skills in Carillion's supply chain which are at increasing risk of being lost."
Mr Kehoe said the organisation in charge of the build, Hospital Company (Liverpool), was trying to work with existing sub-contractors and former Carillion staff "because they have the best understanding of the work that is required to finish the job".
However, he said "highly complex" negotiations were taking time because many were facing financial difficulties as a result of Carillion's collapse.
Mr Kehoe said: "Given this situation, we expect a significant delay and it will prove challenging to get the new Royal finished before the end of the year."
The new hospital is being built next to the existing Royal Liverpool, which will be demolished once the new site opens.
Mr Kehoe said the Royal Liverpool and Broadgreen University Hospitals NHS Trust "was doing all it can" to minimise the completion delay including liaising with the Department of Health.
He said: "We all want the best for our patients and the people of Liverpool and that is to move into our world-class new hospital."
A Department of Health and Social Care spokesman said health minister Steve Barclay had held a "constructive discussion" with Mr Kehoe on Monday.
He said: "Along with the hospital regulator NHS Improvement, we will continue to support all NHS organisations involved to ensure there are plans in place to keep any construction delays to a minimum."
Carillion employs 43,000 staff globally, about half of them in the UK where it did most of its business. It also operated in Canada, the Middle East and the Caribbean.
The British Medical Association, which previously said the company's collapse raised "serious questions about PFI deals and the tendering of NHS services", tweeted that "both patients and staff need urgent answers on when construction will resume".