The Department of Health has defended NHS organisations that have signed cut-price energy contracts that allow gas supplies to be cut off with minimal warning.

The DH has reassured patients that hospital chiefs are only allowed to sign such agreements if stand-alone energy supplies are in place in the event of a network power outage, adding that in such circumstances, energy companies provide ample warning in order for supplies to be switched over.

Following the revelation on that some 100 NHS organisations had signed the agreements, the Observer reported that these included St Bartholomew’s, the Royal London Hospital and Addenbrooke’s.

A health campaign group said it was “beyond belief” that many NHS hospitals have signed cut-price energy contracts that allow gas supplies to be cut off with minimal warning.

Health Emergency said the agreement of “interruptible” contracts at many high-profile establishments allowed energy companies to cut off supplies, potentially putting patients at risk in the pursuit of cutting costs.

Although many UK hospitals rely on back-up diesel generators in the event of a power outage, Health Emergency chairman Geoff Martin said the consequences of a hospital’s stand-alone facilities failing were “too horrific to contemplate”.

Mr Martin said: “This is all part of the massive cuts drive within the NHS that has seen administrators encouraged by outside accountants to save money by signing contracts that mean they cannot rely on gas supplies from one day to the next.

“It is beyond belief. Hospitals may have back-up generators, but the consequence for patients and hospital staff should they go wrong is too horrific to contemplate.”

But a Department of Health spokeswoman said: “NHS organisations can only have an interruptible gas contract if they can show that they have an alternative fuel source available such as oil.

“Occasionally they will be contacted, in advance, and asked to switch to their alternative fuel supplies for a fixed length of time. The nature of the switching is likely to be such that it will not be noticed by patients, visitors and staff.”