A bumper pre-Christmas price war on alcohol among major supermarkets has sparked fury within the pub trade.
Despite the threat of government intervention, major supermarket chains are slashing prices on beer, wine and spirits to entice Christmas shoppers.
But Liberal Democrat MP Greg Mulholland has branded the deals "completely unacceptable" and today tabled a parliamentary motion about the issue.
One leading pub operator has also warned the industry could face an "horrific" Christmas and New Year.
Sainsbury's is currently offering a one litre bottle of Bacardi Superior for nearly half price - £12 - reduced from £20.99.
A 70cl bottle of Bombay Sapphire gin is also being advertised for £12, down from £17.49. And 24 cans of either Carlsberg, Carling, Strongbow were being offered for £12.
Tesco is also selling two bottles of 70 cl Smirnoff Red vodka for £20 and a one litre bottle of Baileys for £15.
Asda and Morrison's are also offering a host of deals.
Tony Brookes, of the Head of Steam pub group, which owns eight venues, said the supermarkets' behaviour was "absolutely deplorable".
"They are sticking two fingers up to everyone except their customers," he said. "The government is so lily-livered on this issue."
Brookes argued the supermarkets should be more socially responsible by doing deals on other products - such as bread and eggs. "Why don't they sell turkeys for 50p instead," he said.
Brookes added: "It's going to be a very tough time for pubs, with the VAT rise in the New Year and then brewers putting up their prices."
Michael Kheng, director of Kurnia Group, which owns five pubs in the Lincolnshire area, said the supermarkets' behaviour was "outrageous".
He added: "How can they justify selling a legalised drug below-cost? The government seems reluctant to do anything, but they must wake-up to this issue."
The coalition has vowed to ban below-cost sales of alcohol - but admitted it will only happen now "if necessary" and not until May 2012.
Mulholland, chairman of the All-Party Save the Pub Group, said: "It is completely unacceptable that some supermarket chains are offering irresponsible alcohol promotions for Christmas.
"This flies in the face of commitments they have made and the government must look at tackling this, introducing a ban on below cost selling as soon as possible."
However, both Tesco and Sainsbury's defended the offers.
A spokesman for Tesco said: "We are coming up to Christmas, purse strings are tight and people are looking to save money. People do have parties around Christmas time. We are not just doing special offers on alcohol either, but things like Pringles and Sprite."
A Sainsbury's spokesman said: "It is important to remember that the overwhelming majority of our customers buy alcohol as part of their weekly shop and drink responsibly in their own home."
Gavin Partington, head of communications at the Wine and Spirit Trade Association, said: "There's no evidence to suggest that price is linked to irresponsible consumption."