The two men, in their 30s, left staff at the upmarket Embassy nightspot in Mayfair with hefty tips after going head-to-head to see who could accrue the larger bar tab.
The multimillionaires, who are believed to have made their money in the oil industry, were accompanied by an entourage of around a dozen friends when they arrived at the venue.
But witnesses said they were joined by a gaggle of freeloaders as the dare escalated to incredible proportions. There was so much alcohol — including vintage champagne — that around one-third of the bar bill ended up being poured away when the men left at 3am this week.
A venue spokesman said: “Nobody could quite believe what was happening – the two clients seemed to be trying to outdo each other.
“One ordered five bottles of champagne, so the next one upped it to six, then to seven, and so on.
“It was incredible. The men didn’t end up drinking that much of it themselves — it was mostly consumed by the lady friends they had met inside on the night.”
Neither man has been identified, though their bar bills came to £66,778.91 and £64,279.70 – making a grand total of £131,058.61.
The bar bills included 30 magnums of Cristal Brut champagne, at £1,380 a bottle, 84 bottles of Dom Perignon, 12 bottles of Dom Perignon rose, several shots of 18-year-old Glenmorangie single malt whisky, champagne-based cocktails and bottles of Peroni lager.
The spokesman said, “Even for Mayfair, the amount they spent was extremely high. The two men left in good spirits, they weren’t legless or anything.”
He said the venue was happy to honour a request from the customers to keep their identities private.
* The bill for £66,778.91 included 30 magnums of Cristal, 20 bottles of Dom Perignon, 20 ‘crack baby’ shots, six espresso martinis, 10 shots of 18-year-old Glenmorangie whiskey, eight bottles of water, seven bottles of 1998 vintage Krug champagne, and two magnums of Belvedere vodka.
The other bill for £64,279.70 included 64 bottles of Dom Perignon at £325 each which came to £20,800 on its own. There were 25 bottles of Cristal champagne, 16 of Armand de Brignac Ace of Spades champagne, 12 bottles of Dom Perignon Rosé, seven mojitos, 10 bottles of Peroni, 20 cans of Red Bull, six bellinis, six bottles of water, two bottles of Chivas whiskey, six bottles of Krug Grande Cuvee, and eight bottles of Belle Époque Rosé.