Less than half the roof of a crumbling hospital has been checked for defects, while almost 200 props are already in place to support it.

Board members at the Queen Elizabeth Hospital in King's Lynn heard some 40pc of the reinforced concrete planks which were used when the hospital was built 40 years ago have been tested.

Some 194 props have been installed in areas of the hospital, 40 of them in the critical care unit.

Chris Benham, the hospital's director of finance, said a "tap and test" survey was only partially-completed, with 60pc of the building remaining to be checked.

In a report to the meeting, he added "The trust has been informed that an emergency capital allocation of £20.6m has been made to address year one of a three year fail-safe programme that will mitigate the risk associated with the structural integrity of the roof and therefore improve safety."

The hospital's risk register, which was reviewed at the meeting, states: "There is a direct risk to life and safety of patients, visitors and staff due to the potential of catastrophic failure of the roof structure due to structural deficiencies."

Mr Benham's report said the trust had submitted "a compelling case" for a new hospital to central government, but had not been included in the list of 40 included in a 3.7bn package of new builds and improvements announced in the autumn.

It now hopes to be one of a further eight schemes set to be approved after a government sending review in November. An announcement on how trusts can bid for funding is expected soon.

QEH chief executive Caroline Shaw said in a report to board members: " The trust continues to receive the backing of local MPs, regional media and other external influencers for its bid to secure a long-term solution to the challenges posed by an ageing estate.

"The team permanently on site to systematically check and manage our buildings and act on any work that might be needed helps to ensure that we can continue to treat patients safely, as normal."

More than 6,000 people have signed our online petition calling for the QEH to be replaced.