The Ritz Club is suing Safa Abdulla Al-Geabury for the money, plus £200,000 interest, which is building at a rate of £438 a day, after his cheque bounced last year.
However, the Swiss national has countersued for £5.4million to cover the sums he blew at the Mayfair casino over four years saying bosses should have stopped him betting because they knew he was hopelessly addicted.
The High Court heard yesterday that in 2009, in a bid to beat his habit, Mr Al-Geabury, 52, signed self-exclusion forms banning himself from a host of London casinos, including The Ritz.
However, the former currency dealer, who rents a £90,000 a year flat in Chelsea, was let back in after several months and gambled again. In court he claimed The Ritz Club “chased” him to keep visiting the casino.
He also alleged he only went to the casino in February last year after accepting an offer to watch Arsenal play Bayern Munich at the Emirates stadium in London.
He claimed a Ritz executive suggested he went to the casino after the match even though he protested. Mr Al-Geabury told the court: “I told [the man] I was a problem gambler.”