Entain's boss has warned Rachel Reeves to be ‘very careful’ amid speculation over a potential tax raid on the gambling industry. 

Former Prime Minister Gordon Brown has suggested a tax on the sector could pay for the Government to scrap the two-child benefit cap, helping to lift families out of poverty. 

But Stella David, who runs the Coral and Ladbrokes owner, warned the Chancellor that such a move could drive people to unregulated operators. 

David, 62, told analysts yesterday: ‘Driving up tax rates has the potential of reducing the tax take because people go to the black market.’ 

Entain yesterday said that revenues rose 3 per cent to just under £2.6billion for the first six months of the year. 

Its online business has been boosted by the Women’s Euros and the Club World Cup while this year’s Wimbledon saw the most ever betting for the annual tennis tournament.