THE Scottish Tories were last night accused of being hypocritical "wreckers" after they urged Europe to challenge the SNP's plan to end the sale of bargain booze despite backing it themselves.

Just days before his party is due to vote in favour of the Scottish Government's bill to set a minimum price for alcohol at 50p per unit, deputy Tory leader Jackson Carlaw nevertheless called on other EU countries to raise potentially fatal objections to it when they examine the fine print later this year.

Carlaw insisted he was not trying to wreck the Alcohol (Minimum Pricing) (Scotland) Bill, which is set to complete its passage through Holyrood on Thursday, and only wanted it thoroughly tested legally.

But one SNP MSP said the "gobsmacking" move was clearly meant to wreck the plan by the back door.

After long querying its legality, the Tories only recently agreed to support the minimum pricing bill in return for a sunset clause which would see the law lapse if it failed to deliver results, and a concession to "notify" the EU of the idea.

Health Secretary Nicola Sturgeon had previously resisted notification, as it lets the EU Commission and EU countries delay or block measures seen as interfering with free trade.

Carlaw, who travels to Brussels next month to meet members of the drinks industry worried about minimum pricing, said he feared unless the idea was challenged by another EU country, it would be allowed to proceed without proper scrutiny.

Urging other countries to get involved, he said: "It is vital that minimum pricing is given a robust MOT to ensure it does not break EU free trade rules. So to ensure that the EC expresses a view, Scottish Conservatives intend to meet and encourage concerned member states to mount a challenge so we can have clarification from Europe on the legality ... If it works then we will be delighted that we aided that success. If it fails then we have secured the mechanism by which it can be dropped."

But SNP MSP Gil Paterson, who sat with Carlaw on Holyrood's health committee as it examined the bill, said: "You can't camouflage a wrecking process. I'm gobsmacked that that's his attitude. I thought that, although he had legitimate questions, he was interested in achieving a good outcome. I'm disappointed he's gone against what he was saying, and he's trying to wreck it."

But critics have always claimed the step could fall foul of EU competition law, although ministers believe it is EU compliant, as it can be justified as "proportionate" on health grounds.

In the autumn, ministers will lay regulations at Holyrood setting out the details of the scheme, triggering notification to the EU and a three month "standstill period" during which the commission "may react" to the idea. If objections are raised, there is another three-month period to iron out problems. If there is no agreement after that, the commission can put the plan on ice for a year. The first response from Brussels is now likely in 2013.

The government could also face legal challenges in domestic courts from companies affected by minimum pricing.

A Scottish Government spokeswoman said: "Minimum pricing of alcohol does comply with European law, provided it is justified on the basis of public health and social grounds. We are confident that it is justified in Scotland."