Two senior officials resigned from Nigel Farage's Reform UK on Friday as the party was reported to the police over fresh allegations it flouted donation rules.
Farage's aide Dan Jukes and Reform's head of policy James Orr stepped down, the party said.
Reform UK has been reported to the Metropolitan Police and the Electoral Commission over illegal donations. The Liberal Democrats Cabinet Office spokesperson Lisa Smart said the case involved "the acceptance and concealment of a donation from an impermissible donor."
The complaint follows an undercover investigation aired by UK broadcaster Channel 4 News from a company called Verbatim who captured members of the Reform party discussing donations from the son of an American financier who is actually an undercover reporter. Under UK law, donations from foreign investors are illegal.
The ruling Labour party has also said it intends to report the matter to the police.
