Two Reform UK officials have stepped down and the party has launched an investigation following allegations they breached political donation rules by having polling paid for by an overseas company.

James Orr and Dan Jukes have stepped down from Reform, a party spokesperson said.

Rival parties had reported Reform to the police over claims by Channel 4 News that Reform took funding from a US firm for three polls it commissioned earlier this year, costing £32,500.

A Reform UK spokesman said: “Reform UK has launched an investigation following the broadcast of a Channel 4 News programme.

“Both individuals involved have stepped down from their respective positions pending the outcome of the investigation.

“The party believes it is important that the investigation is allowed to proceed independently and without prejudice. No further comment will be made while the investigation is ongoing.”

Reform UK chairman Lee Anderson told Sky News there was “no chance” of them returning to the party.

It comes as Reform is gathering its members in Birmingham for the party’s annual conference, billed as setting out the party’s plans for its first 100 days in office should it win the next election.

During his speech at the party conference, Reform party leader Nigel Farage is expected to pledge to make the UK parliament sit seven days a week in a bid to “fix” Britain.

But his speech risks being overshadowed by the allegations that the party breached political donation rules by having polling paid for by an overseas company.

Foreign companies are not a permissible source of funding for parties, including for payments for studies and research, and accepting donations from them could constitute a criminal offence.

Labour Party chairwoman Bridget Phillipson has called on Mr Farage and his team to “urgently prove” that they had not “broken the law and secretly plotted to undermine our democracy”.

In a letter to the Metropolitan Police, Liberal Democrat Cabinet Office spokeswoman Lisa Smart said the allegations raised “alarming questions about whether there has been a wider complacency toward foreign interference by the individuals involved”.

Reform has denied any wrongdoing and insisted it has a “robust vetting process” for donors.