Richard Tice is under investigation by the parliamentary standards watchdog for allegedly failing to declare an interest.

The standards commissioner, Daniel Greenberg, confirmed on its website that an investigation had been opened into allegations against the Reform UK deputy leader on Tuesday last week.

Mr Tice has claimed a parliamentary investigation opened last week relates to a complaint over “whether I should have referenced my register of interests at the start of a debate on UK democracy and Israeli influence”.

Without naming the group he was referring to, he wrote on X: “Contrary to garbage in media: Standards Commissioner is considering complaint by anti semitic anti Israel lobby group over whether I should have referenced my register of interests at start of a debate on UK democracy and Israeli influence.

“The same anti Israel group failed to notify Commissioner that Ayoub Khan MP did not declare his substantial donation received from a pro Palestine group. Funny that…..”.

The probe comes just days after the standards watchdog declined to investigate a complaint relating to an undeclared loan of almost £80,000 from convicted fraudster and Nigel Farage ally George Cottrell.

Mr Tice wrote on X that the earlier claim was “so stupid” that the commissioner had “thrown it out in under 24 hours”. The post was published the day after the commissioner launched the separate probe into his alleged failure to declare an interest.

Labour said the latest accusation shows it’s “clear Reform think the rules just don't apply to them”.

“The Reform sleaze scandals continue to pile up,” a Labour Party spokesperson said.

“Richard Tice is now under investigation by the Standards Commissioner, on top of his firm avoiding paying £600,000 in tax. This means that both Reform's leader and deputy leader now have standards investigations hanging over them.

“With police probes, Nigel Farage's secret £5 million gift, and reports of funding from a convicted fraudster - it's clear Reform think the rules just don't apply to them.”

The party has been dogged by questions about its funding in recent weeks.

Mr Farage announced he will quit as MP for Clacton to stand in the ensuing by-election after questions mounted about a separate £5 million gift he received from crypto-billionaire Christopher Harborne and gifts from a convicted criminal, Mr Cottrell.

The party leader has billed the by-election, likely to take place on August 13, as a “people versus the establishment” contest.

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