Health Secretary Alan Johnson has ordered the hospital trust at the centre of a superbug scandal to withhold any severance payment to its former chief executive.

Mr Johnson stepped in amid rumours that Rose Gibb received a large payout after stepping down on Friday as head of Maidstone and Tunbridge Wells NHS Trust.

Mr Johnson said: "I have instructed the trust to withhold any severance payment to the former chief executive of Maidstone and Tunbridge Wells NHS Trust, pending legal advice."

Ms Gibb left the trust by mutual arrangement after four years in charge. Annual accounts showed she earned around £150,000 in salary, £5,000 benefits and £12,500 in pension in 2006/07.

The Health and Safety Executive (HSE) and Kent Police are currently investigating whether to take action against the trust and Ms Gibb as an individual.

The move comes after appalling hygiene standards at Kent and Sussex Hospital, Pembury Hospital and Maidstone Hospital saw Clostridium difficile directly linked to 90 deaths.

The infection contributed to a total of 345 deaths and more than 1,100 infections across a two-year period.

The worst two outbreaks were in the autumn of 2005 and early 2006, a damning official report revealed.

Dirty wards, inadequate staffing levels and too much focus on debts and Government targets all contributed, the study revealed.

The outbreaks at Maidstone and Tunbridge Wells NHS Trust were the worst yet seen in the UK.

The watchdog's report has been sent to the Health and Safety Executive and Kent Police, who will decide if there are grounds for criminal charges.

Health Minister Ann Keen said: "I would like to offer my sincere condolences to the patients and families who have been affected by these outbreaks. This type of failure must not be repeated.

"Trusts must deliver clean, safe treatment to every patient, every time and where senior management and trust boards fail to act, they must be held accountable."

Doreen Ford, 77, the mother-in-law of former Bucks Fizz star Cheryl Baker, died at Maidstone Hospital from septicaemia while infected with the bug.

The singer and TV presenter has called for the hospital to stop admitting patients who were vulnerable to C diff.

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