Mr Hosking gave £350,000 to Tory candidates ahead of the 2017 election, but later said he had been “taken in” by the party on Europe and would give a six-figure sum to Nigel Farage’s Brexit Party ahead of its 2019 European elections victory.

He told The Telegraph in a statement: “I am very pleased at the way the party is developing and establishing itself as the leading opponent of the intolerant progressive ideologies emanating primarily from the country’s university system, and encompassing cancel culture, alarmist climate activism and critical race theory.”

It comes ahead of the by-election this Thursday in North Shropshire where Reclaim is standing Martin Daubney, the party’s deputy leader and a former Brexit Party MEP.

Laurence Fox, the leader of Reclaim, said: “What we have seen going back as far as the Gang of Four and the SDP through to the Brexit Party and beyond is that the political Establishment closes ranks through fair means and foul to protect the old order.

“New parties cannot get bank accounts, they face often disproportionate regulatory scrutiny and first past the post is the final guarantor that no challenger gets a look in.

“This is a radical plan aimed at a radical outcome. Without it, the voter is faced with the least worst choice between a Right-wing party that enacts Left-wing policies, and a Left-wing party whose cultural agenda is at variance with almost everyone outside North London.”

Mr Fox, who rose to prominence with his acting career, stood in this year’s London mayoral election on a platform against “extreme political correctness”. He ranked sixth with 1.8 per cent of the vote, meaning he lost his £10,000 deposit.

Nigel Farage, who set up the Reform Party currently led by Richard Tice, suggested last week that Reclaim and Reform should merge “to put some salt on Boris Johnson’s tail”.

There is no suggestion of any wrongdoing. The Electoral Commission declined to comment.

A source said: “Donations have to be from permissible donors and reported by the party to the Commission so they can be published for transparency.

“We don’t regulate how parties spend their money, though before an election there is a regulated period where spending limits apply.”