Health secretary Andrew Lansley has ordered an investigation into NHS South West’s role in the sacking of a trust chief executive.

NHS chief executive Sir David Nicholson will look at the strategic health authority’s activities in relation to Royal Cornwall Hospitals Trust, whose chief executive John Watkinson was sacked last year. The SHA’s chief executive, Sir Ian Carruthers, was interim NHS chief executive before Sir David was appointed.

It has been a traumatic time,” he said. “I knew that I had done a good job and I believed that I had been dismissed unfairly

John Watkinson

The Department of Health said today the outcome of the investigation would be made public and it was likely to take “weeks rather than several months”. It will be carried out by a third party, commissioned by Sir David, but details of this have yet to be confirmed.

An employment tribunal has ruled that Mr Watkinson was unfairly dismissed and that his actions in obtaining legal advice about cancer services reconfiguration had been “a severe irritant to the SHA’s intentions” and that he was “to be got rid of”. Although Sir Ian’s actions in relation to Mr Watkinson and the reconfiguration were frequently mentioned in evidence, Royal Cornwall Hospitals Trust did not call him as a witness.

Last week, a former interim chair of the trust, John Mills, told the BBC the board had come under pressure from the SHA to remove Mr Watkinson or face removal themselves. The SHA denied putting pressure on the trust to dismiss Mr Watkinson and the trust said that if members of the trust board had felt unacceptable pressure to act in a way that was inappropriate they should have said so at the time. “Submitting to any such improper pressure and not speaking out at the time would have been a serious failure of duty,” it said.

“We were firm that the trust conducted an independent review, the findings of which concluded that the trust was headed towards corporate failure. It was these conclusions that led the trust board, acting on independent legal advice, to dismiss John Watkinson,” said the SHA.

“Sir Ian Carruthers OBE has an exemplary 41-year track record of outstanding service to the NHS, including acting as national NHS chief executive in 2006. We welcome the report announced by the secretary of state and will of course offer every assistance.”

Mr Watkinson welcomed the investigation but said he would have preferred it to be completely independent.

He now faces a £200,000 legal bill: any awards he receives from the trust will be used to part-pay this. His home in Cornwall is on the market as he can no longer fund it without a job.

“It has been a traumatic time,” he said. “I knew that I had done a good job and I believed that I had been dismissed unfairly for whistleblowing.”

He said he pressed on with the employment tribunal because clearing his name was crucial to getting another job.

“There were a number of decision points along the way. I had to keep deciding whether it was right to carry on and that was the most stressful thing - could I justify spending that amount of money?” he said.