Rishi Sunak has pulled support from candidates Craig Williams and Laura Saunders over the General Election betting row.

The Prime Minister acted after coming under mounting pressure within the party to take a tougher stance on the alleged use of inside information to bet on the timing of the July 4 poll.

In a sign of the wider scope of the Gambling Commission’s investigation, the watchdog passed information to the Metropolitan Police alleging that five more officers had placed bets related to the timing of the poll.

The row has overshadowed the Tory election campaign in recent days as Mr Sunak battles to close his party’s 21-point average poll deficit to Labour.

Mr Williams, who was the Prime Minister’s parliamentary aide, and Ms Saunders who is standing in Bristol North West, will no longer have the support of the party.

Because nominations have closed, Mr Williams – who is standing in Montgomeryshire and Glyndwr – and Ms Saunders will both still be on the ballot paper.

But a Conservative Party spokesman said: “As a result of ongoing internal inquiries, we have concluded that we can no longer support Craig Williams or Laura Saunders as parliamentary candidates at the forthcoming General Election.

“We have checked with the Gambling Commission that this decision does not compromise the investigation that they are conducting, which is rightly independent and ongoing.”

Meanwhile, Scotland Yard said five more officers – in addition to a member of Mr Sunak’s protection team who was arrested earlier this month on suspicion of misconduct in a public office – were alleged to have placed bets.

The officers are based on the Royalty and Specialist Command, the Parliamentary and Diplomatic Protection Command and the Central West Basic Command Unit, but none of them work in a close protection role.