The money, which was part of an overall underspend of more than �400m, has been diverted into other budgets including forestry and Historic Scotland.

The Scottish NHS needs every penny that is available to it

Kay Ullrich, SNP MSP

The announcement led to strong criticism from the Scottish National Party and overshadowed Health Minister Susan Deacon's pledge to invest more than �8m in recruiting 300 specialist NHS staff.

The SNP said it was astonishing that the health minister did not spend all the available money when the NHS was in crisis during last winter's flu outbreak, which severely stretched many health trusts.

SNP health spokeswoman, Kay Ullrich, said: "It is a ludicrous state of affairs that on the day the health minister allocates an extra �8m to the health service, Jack McConnell announces that he is clawing back �34m out of the health budget - over four times the amount.

"On the minister's own figures, this would be enough to fund more than 400 additional doctors, and an extra 800 specialist nurses.

Kay Ullrich: "Ludicrous state of affairs"

"The Scottish NHS needs every penny that is available to it. Money allocated to health should be spent on health - that is a clear need that the Scottish people know only too well."

However, Mr McConnell, who made the disclosure in a parliamentary answer, stressed that there was an underspend every year.

The minister said a quarter of the �400m-plus savings were made in the NHS and �100m of the �135m would be retained for health service spending.

He also dismissed suggestions that money was being lost to the health service.

He said: "One hundred and seventy three million pounds of extra money for the health service this year on top of the Budget and today you see, through efficient management of the health service resources, another �101m able to be retained by health departments, trusts and boards in order to spend on services this year."

Jack McConnell: Taking back money not spent

"That's good management of resources. People across Scotland do not want to see managers spending money unnecessarily at the end of a financial year when they could spend it more efficiently in the months ahead."

The Scottish Tories accused the executive of mismanagement and said the �8m investment had been undermined by Mr Connell's disclosure.

Health spokeswoman, Mary Scanlon, said: "It is absolutely outrageous that overall, the NHS can be underspent by �135m at the end of a year when individual health boards and trusts have been struggling to reduce their financial deficits exacerbated by the executive's mismanagement of the winter flu crisis.

"Patients are paying the price of this underspend in the health budget through longer waiting times and waiting lists."

Earlier, Ms Deacon announced that an extra 100-plus doctors and 200 specialist nurses would be recruited in an attempt to reduce waiting times and avoid another winter beds crisis.

Addressing a conference in Glasgow, she said �8.4m would be invested in the staff, part of the extra �174m the Scottish Executive was given to spend on health in the chancellor's last Budget.