LONDON (Reuters) - Britain’s ruling Conservative party has blocked an attempt by leading Brexit supporter Arron Banks to become a member in the hope of trying to get a hardline Brexiteer elected as party leader if Prime Minister Theresa May steps down.

Arron Banks and Andy Wigmore, who ran the Leave.Eu pro-Brexit referendum campaign, arrive to give evidence to the Digital Culture Media and Sport Parliamentary Committee in London, Britain, June 12, 2018. REUTERS/Simon Dawson

Businessman Banks, who bankrolled one of the main “Leave” campaigns in Britain’s 2016 EU membership referendum, had called on his supporters to follow suit to pack Conservative ranks.

If May were to resign or be toppled, the party grass roots membership would have the final vote on electing her successor.

“Arron Banks has today joined the Conservatives to ensure he has a vote on the inevitable leadership contest,” the Leave.EU group, which Banks chairs, tweeted on Thursday.

But a Conservative party spokesman later said in a statement: “Arron Banks’... application for membership of the Conservative Party has not been approved.”

Last month, May unveiled plans to keep Britain linked to European Union mechanisms on issues such as customs, angering those who favor a clean break from the EU and its institutions.

May wants to lead the Conservative Party into the next general election, which is due in 2022, but she has faced continued rumors over how long she can survive since losing her parliamentary majority in a snap election last year.

After three months of membership, Banks would become eligible to vote in any leadership contest the party might hold.

In such a contest, Conservative members are asked to pick from two candidates chosen by the party’s elected Members of Parliament.

Conservative Party membership currently stands at over 124,000 people and is growing, Deputy Chairman James Cleverly said on Twitter on Aug. 22.