HMRC is to come under even greater pressure to tackle the problem of alcohol duty fraud after the National Audit Office announced it had launched an investigation.

The NAO is investigating HMRC's implementation of the alcohol strategy following a Federation of Wholesale Distributors campaign for tougher action to tackle the problem of duty fraud, which some wholesalers blame for a 40% drop in alcohol sales over the past two years.

The NAO revealed the investigation in a letter to the FWD. It said there was evidence that "organised criminal activity" was behind a rise in duty drawback claims a scheme that allows traders to claim back duty on alcohol on the basis it is being sent abroad. The scheme is widely abused with much stock still sold in the UK.

FWD CEO James Bielby recently met the NAO to outline some of the problems faced by wholesalers.

"The FWD noted that, to date, HMRC's response had not been seen to be proportionate to the scale of the problem," said Bielby. "It is good news because it will put more pressure on HMRC to get to the bottom of this problem, which is of such huge importance to HMRC members."

The NAO will report in the summer and the Public Accounts Committee will question HMRC in October.