Gina Miller's tactical voting website Remainunited.org is not recommending a tactical vote to unseat Boris Johnson in Uxbridge and South Ruislip, writes Christian Smith.

The businesswoman, no stranger to controversy, rose to prominence in 2016 when she launched a legal challenge to the government over Brexit.

A poll for Best for Britain over the weekend suggested fewer than 41,000 voters in marginal seats would need to vote tactically to deny the Conservatives a majority.

Ms Miller said: “In Uxbridge and South Ruislip [the willingness to tactical vote] has been on the low side compared to other constituencies.

“Psychologically, people start concentrating on the Monday leading up to the Thursday.”

Now promoting tactical voting in her third election, Miller criticised her competitors, claiming that some did not calculate their recommendations seriously enough, while others ‘have a political agenda.’

Expressing her frustration that the websites had not joined forces, she said: “I have tried my best.

“It has been disappointing to me that we haven’t been able to come together more with one objective.

“The [Brexit] side is far more ruthless and our side has had this petty infighting.”

Ms Miller argued that tactical voting sites must keep their recommendations up to date over the course of an election.

Ms Miller said: “Tactical voting is now very much a part of our voting and political landscape.

“It is the only way that you can wipe out a Tory majority.”

Remainunited.org is one of several pro-Remain sites which recommends the candidate most likely to defeat the Conservative contender in any given seat.

She said: “We’ve updated our website seven times already and we have more updates coming because as the campaigns progress, as people become more engaged, people are more volatile than we’ve ever seen before.

“You have to be led by the data.”

Speculation has spread that Boris Johnson’s Uxbridge and South Ruislip constituency could change hands if tactical voting takes effect.

Johnson, who was criticised for not attending the constituency’s hustings last week, won the seat in 2017 with a majority of 5,034, the smallest majority of any sitting Prime Minister since 1924.

The website only offers recommendations if the non-Conservative challenger is sufficiently close to the leading Tory, and where voters are adequately engaged with tactical voting.