The former chief excutive of William Hill, the bookmaker, admitted in the High Court to sending an “inappropriate” and “very silly e-mail” as he answered claims that Britain’s biggest turf accountants colluded to withdraw sponsorship from racecourses.

David Harding, who resigned last year, was being questioned yesterday about an exchange of e-mails with David Hood, director of racing and PR at William Hill, over the decision not to sponsor a race at Newbury, one of 31 racecourses that form part of Amalgamated Racing (Amrac), which is in dispute with the big bookmakers.

In the e-mail exchange, Mr Hood explains to Mr Harding that he has “knocked back” a request to sponsor the race, partly because Newbury is a member of Amrac.

Mr Harding responds that he is happy for his colleague to take “a harder and more specific line with Amrac”, adding: “They've declared themselves to be in direct competition with us, so I see no reason why we should be seeking to help them in any way.”

Mr Hood responds by suggesting that the William Hill boss “might want to give Fred Done [head of Betfred] and Wilf Walsh, [then managing director of Coral] a gentle reminder that perhaps we should all be on the same sheet re sponsorship”.

Mr Harding sends back an e-mail saying: “Will do. Not sure they see things in quite such a joined-up way, though."

When questioned yesterday about the e-mail exchange, Mr Harding insisted he did nothing about it and there was no contact with the group's rivals. But he conceded that it was “inappropriate” and a “very silly e-mail for a chief executive of a PLC to send”.

He added: “It was a very poor thing for a chief executive to do. It was solely about getting it out of my in-tray."

The big bookmakers allege that the Amrac racecourses engaged in price-fixing when they teamed up to sell television coverage of their races to betting shops through a new company called Turf TV.

Amrac, which represents more than half of Britain’s 60 racecourses, lodged a counter claim against William Hill, Ladbrokes and Betfred, claming that the big bookmakers colluded to reject Turf TV and withdraw race sponsorships.

In June last year, Mr Harding said: ”Racing has declared war on us and we are responding ... in a war, you use every means at your disposal - legal, commercial and political.”

The case continues.

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