The stamp scheme was proposed by the chancellor

Treasury Minister John Healey has asked the National Audit Office to look at the figure, cited by Chancellor Gordon Brown as evidence of the need to clamp down on fraud.

The chancellor intends to introduce a stamp scheme to combat duty fraud.

Opponents to the plan claim the move would cost the industry �280m.

The investigation was announced by Deputy Enterprise Minister Lewis Macdonald in a Holyrood debate on the stamp scheme proposal on Thursday.

Mr Macdonald said: "I understand that John Healey has encouraged the National Audit Office to look at the disputed figures for fraud.

"Sir John Bourne, the comptroller and auditor general, has expressed his willingness to do so, which is a move I'm sure will be welcomed by the industry."

A clear message should go out from all parties to ask the chancellor to change his mind and scrap what is a stupid idea Alex Neil SNP MSP

He said the minister was "more than willing" to consider anti-fraud measures suggested by the industry and would work with the industry on ways of keeping costs down if no alternative was found to the stamp scheme.

Tory MSP Brian Monteith, questioned the one-in-six figure quoted by the chancellor and said the best way to cut down on fraud would be to reduce whisky excise.

"If the chancellor were to cut the duty, as has been done in Denmark, then smuggling would be marginalised and revenues would go up," he said.

Jackie Baillie, Labour MSP for Dumbarton, backed Mr Monteith's view.

"I do not believe strip stamps are the answer. They just don't work," she said.