Prospective buyers in the UK will be able to log-on to the Vente-Privee site from 6am on Sunday (11 May) for a chance to purchase Yquem from the 1996, 1998 and 2000 vintages.

It is believed to be the first time Yquem has involved itself in a so-called flash sale, which involves selling wine at a significant discount for a very short time period.

Top Bordeaux chateaux generally sell through the Place de Bordeaux and Yquem's move is further evidence that estates are seeking to increase direct sales to supplement this system. The flash sale also comes amid ongoing muted demand for Sauternes, which fine wine exchange Liv-ex last year called a 'perennial underperformer' in terms of prices achieved on the market.

UK merchant Berry Bros & Rudd was this week offering cases of 12 half-bottles of Yquem 1996 and 1998 for ?,000 each. The 2000 vintage is generally more expensive. Berrys had none in stock, but UK retailer Hedonism listed one half-bottle at 210 pounds.

Yquem could not be immediately reached for comment on the sale. A spokesperson for Vente-Privee said the company was not at liberty to divulge the level of discounts that will be offered. 'The chateau does not want to communicate prices before the sale,' she said.

As far as Vente-Privee is concerned, she added the sale constitutes 'an exciting opportunity' to attract other wines of equal standing to its business model.

'Certain brands always say no, but if someone like Yquem says yes then it's hugely powerful,' she said. It is expected that consumers will be able to purchase the wines by the bottle rather than by the case.

Paris-based Vente-Privee specialises in flash sales on many products, including fashion and travel, and has specific websites for different countries around Europe. It launched a wine division in the UK in March, but has featured wine and spirits on its sites in other European countries since 2006, selling a total of 3.3m bottles in 2013.

In the UK, group cofounder Xavier Court said at a launch event that relatively high duty tax means the average discount on the retail price is lower than in some other markets, at around 30?0% below average market price.