Gordon Brown was urged to approve the long-awaited Birmingham super-hospital today, after a similar scheme in London was finally given the go-ahead.
MP Gisela Stuart (Lab) said she hoped the rebuild of the Queen Elizabeth Hospital in her Edgbaston constituency would now receive authorisation from the Treasury.
Hospital managers revealed the project had already been approved by the Department of Health, but was waiting for the green-light from the Chancellor.
Any further delays could cost £1 million a week, they warned.
The £559 million project, which will create a new 1,249-bed acute hospital, had been stalled while Ministers ordered a review of the redevelopment of St Bartholomew's hospital, in London.
Both projects were to be paid for using a controversial funding scheme called the Private Finance Initiative.
This allows private companies to fund new hospitals, with the NHS paying back the costs over up to 50 years.
But now that St Bartholomew's has received the go-ahead, the Birmingham scheme might finally receive approval.
University Hospital Birmingham NHS Trust, which runs the Queen Elizabeth, has warned that any further delays after the middle of March will push up costs by up to £1 million per week.
It has asked the Department of Health for permission to begin carrying out building work, in a bid reduce extra costs.
Mark Britnell, the Trust's chief executive, said he welcomed the DoH's decision to approve the rebuild.
He said: "We have taken another step forward with this news, but we still await HM
Treasury approval." Ms Stuart said: "They have clearly started the process of approving PFI schemes and I welcome that.
"I very much hope the Queen Elizabeth will be next."
The scheme also includes a new specialist psychiatric hospital to replace the existing hospital in Selly Oak.
Patients' groups yesterday claimed the hold-up at St Bartholomew's, known as Barts, had added an extra £35 million to the project's cost.
Health Secretary Patricia Hewitt said the delays had been essential to ensure large amounts of public money were properly spent.
"Of course it is sensible for us just to double-check that we are getting the best value for taxpayers' money."
Barts was reprieved in 1998 as part of a £1 billion programme to modernise health-care in the capital.