The Royal Free Hospital has lost millions of pounds because of a dodgy computer system introduced this summer.

The Hampstead hospital, which treats patients from Barnet, reported a half-yearly budget deficit of £7.7 million last week and attributed blame for almost all of it to the Government-backed Cerner Millenium system.

The system, which went live in June, is designed to manage appointments and hold patient information electronically, but has been plagued with problems from the start.

A report released by the Trust last week reveals that it lost £3.78 million because data had been entered wrongly, £1.32 million because appointment slots had not been filled and has forked out £1.23 for additional staffing to cope with the problems.

A spokesman for the Trust said: “Measures are in place to ensure that the services and standard of care offered to our patients are not compromised.

“We are in discussions with NHS London and the London Programme for Information Technology on when and how our costs can be recovered."

The hospital was the first in London to go live with the system, created by the US IT firm Cerner and supplied by BT, and the Department of Health intends to expand it across the UK.

However, at the end of last month the London Strategic Health Authority, which manages the NHS in London, put the brakes on plans to roll out the system across the capital until the problems at the Royal Free have been resolved.

A spokeswoman for NHS Connecting for Health, which is tasked with improving computer systems in the NHS, said: “We support NHS London, London Programme for IT and BT in their decision to take stock of current implementations at London trusts.

"We agree that learning from those experiences is an important next step in successfully introducing information systems to support patient care across acute settings."

Stephen O’Brien, a shadow minister for health, criticised the Government for allowing more money to be lost on top of the £12.4 billion earmarked for the project nationwide.

He said: “It is a disgrace that ministerial incompetence is leading, once more, to hospitals losing money.

"This cash should be used for caring for patients – instead it is pouring into the black hole of the Government’s supercomputer.”