Legal action by the drinks industry could delay the introduction of minimum pricing for years - or even scupper it completely, according to industry sources.

This week the Scotch whisky Association, representing companies including Diageo, Chivas Brothers and Glenmorangie, made a complaint to the EC and called for a judicial review in Scotland over plans to introduce a 50p per unit minimum price.

The move will spark a chain reaction that will affect plans north and south of the border, with the WSTA planning a separate challenge, along with the European Spirits Organisation (CEPS) and Comité Vins (CEEV), the European wine body.

The EC has until September to decide whether to investigate. If it does, the UK government, as the member state, will become embroiled in what could be a marathon inquiry.

Diageo called on the government to publish its evidence on the legality of minimum pricing, while the OFT also cast new doubt, saying that it “may raise issues of compatibility with European free movement laws.”