WARNINGS over the finances of NHS Tayside were not "taken seriously", the head of Scotland's public spending watchdog has said.

Caroline Gardner, the Auditor General for Scotland, also confirmed that internal auditors had flagged up as an "unusual transaction" the use of £2.7m in charity cash to retrospectively pay for projects, including IT systems, that the NHS had previously agreed to fund from the core budget.

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The Herald revealed that trustees of NHS Tayside's endowment fund had agreed to release the funds in 2014 after the health board ran out of money.

The health board had to temporarily suspend its constitution to allow the transfer to proceed as it breached its own rules.

Giving evidence to Holyrood's Public Audit Committee, Ms Gardner said auditors had flagged that "as being something which was an unusual transaction which played into the growing picture of financial pressures at NHS Tayside".

She said: "Internal auditors raised concerns about the retrospective transactions back in 2014 and it is included in the external auditors report as well.

"There is a significant question about why, throughout the NHS system, warnings from auditors are not being taken seriously. The reason why is something you would need to ask of Scottish Government and of the board itself."

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Sources previously told the Herald that the internal auditors from NHS Fife and Forth Valley had come under pressure from NHS Tayside executives in 2014 not to "rock the boat", with an implication that they risked losing the auditing contract if they caused problems.

In the wake of the charity cash row, NHS Tayside chair Professor John Connell, in place since 2015, resigned and chief executive Lesley McLay - who was chief executive at the time of the 2014 transfer - has taken sick leave.

Health Secretary Shona Robison described Ms McLay's position as "untenable", making her return to work unlikely.

Their posts are being filled on an interim basis by John Burns and Malcolm Wright.

Since 2012, NHS Tayside has been bailed out with £45.3 million of Scottish Government loans to help balance the books.

This will increase to £48m after the Scottish Government agreed to loan NHS Tayside an additional £2.7m to repay the charity cash to its endowment fund.

It follows a review by accountants Grant Thornton which found that NHS Tayside had "misrepresented" its financial performance for six years by "holding" £5.3m in eHealth funding instead of spending it.

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Questioning Ms Gardner, former health secretary Alex Neil suggested other health boards may also have fudged their finances.

He said: "It seems to me it is inevitable that other deals will have been done that have so far not come to light. I do not believe as a former health secretary this was a one-off deal."

Ms Gardner was unable to assure him this was not the case.