Millions of pounds are missing from an NHS trust budget, which could have far reaching consequences for patients, health experts warned.

An independent review has been commissioned into the 2010-11 accounts for NHS Croydon after a massive deficit of up to £25m was discovered by its financial team.

The discovery of the shortfall comes only four months after an independent audit of the accounts.

Geoff Martin of London Health Emergency, an independent watchdog, said: “In the run up to the busy winter months NHS Croydon patients will die unnecessarily as a result of this.

“I think the people responsible who created this crisis and have presided over it should be forced to resign.”

He said he believed the level of debt could be as high as £38m, and this had resulted in a freeze on spending for the rest of the financial year.

He said: “In some respects the level of deficit isn’t important. The main thing is in the run up to winter they are going to make huge cuts, which is going to drastically affect the level of care.

“Winter is the busiest time of the year with cases of the flu and respiratory problems placing huge pressures on the service.”

NHS Croydon is part of a recent merger between Kingston, Richmond, Sutton and Merton and Wandsworth, called South West London NHS Trust.

Michael Walker, south-west London regional officer for Unison Health Care said: “These losses have come from NHS Croydon before the merger took place. The fact is probably 75 per cent of this money would have gone to Croydon University Hospital and potentially this loss could see wards close, and nurses lose jobs.”

A spokesman for South West London NHS Trust admitted it had a “significant budgetary challenge,” resulting in the commissioning of an independent review of last year’s accounts.

She said: “In Croydon PCT we are developing a detailed action plan to get back into balance and ensure robust financial planning for the future to live within our allocated resource. It is our aim to manage this deficit within existing financial resources as far as possible.”