A high-profile NHS manager could be forced to pay back a six-figure sum after securing the top job at one of Scotland's flagship trusts within weeks of leaving Wales' largest provider.

Lothian and University Hospitals trust in Edinburgh announced last week that Allister Stewart, former chief executive of University Hospital of Wales trust, would start as chief executive on 1 July.

He had been widely expected to lead the merged University Hospital of Wales and Llandough Hospital trust.

But days before it started work the board 'decided not to offer the chief executive's post to either of the two candidates' - the other being Llandough Hospital and Community trust chief executive Dr Norman Mills.

A statement added: 'In coming to its decision, the appointment board had been informed that Mr Stewart was anxious to further his career elsewhere.'

The Cardiff trust confirmed last week that Mr Stewart had been entitled to severance pay.

Unions reacted furiously to reports that Mr Stewart would receive two years' salary, which the trust put at£75,000 a year plus benefits, making a payoff in the region of£150,000 to£200,000.

But a trust spokesperson said on Monday that Mr Stewart 'would be subject to clawback' if he started work in Edinburgh 'on the date planned'.

Mr Stewart had strongly defended his position. He confirmed widespread reports that he was unhappy about the treatment of UHW chair Derek Morgan, who lost the combined trust chair to Llandough's David Durham.

But he insisted that he had been prepared to take the combined trust job and was 'disappointed' not to be offered it.

Once he found himself 'unemployed' he was approached about the Edinburgh appointment, he told HSJ. 'I only got what I was legally entitled to. I have not done anything wrong,' he said. 'I was unemployed. And then I got another job in a short space of time.'

Lothian University Hospitals trust first advertised for a chief executive almost a year ago. The job initially went to Malcolm Stamp, chief executive of Norfolk and Norwich Health Care trust, but he pulled out in January for 'unforeseen family reasons'.

HSJ sources say it has been difficult to appoint to the post as the trust is at the centre of a row over a private finance initiative replacement for Edinburgh Royal Infirmary. But Mr Stewart, who was chief executive of Grantham and Kesteven General Hospital in the wake of the Beverly Allitt case, said: 'The glare of publicity is something I have worked in all my life.'

He is no stranger to PFI, having seen a strike by UHW sterile services staff over transfer to the private sector under PFI.