Ukip MP Douglas Carswell has denied he helped the Conservative general election campaign in South Thanet by passing information about voters to the party.

The allegations, which have been made by a company owned by Arron Banks, a key donor to Ukip, have been passed to Kent Police

In a letter setting out the claims, the company says the Conservatives were passed the data for South Thanet by the MP, enabling them to do what is known as “push polling” of key voters.

Mr Carswell said:

“There is no basis for these claims whatsoever. We should just be relieved that those responsible for the disastrous campaign in South Thanet were not responsible for the successful referendum campaign.”

The company Precision Risk & Intelligence said it had evidence to corroborate its claims, according to a report in The Guardian.

The general election battle in South Thanet saw a close-knit fight between the Conservatives and Ukip, with Craig Mackinlay eventually defeating party leader Nigel Farage.

In a statement, Kent Police said: “Kent Police received a letter on 23 August regarding our on-going investigation into election spending. The letter will be passed to the investigators for their consideration.”

The force is already investigating claims about excessive spending by the Conservatives during the battle for South Thanet.

Conservative Central Office declined to comment.