Nigel Farage has dramatically resigned as an MP and will fight a by-election to retake his Clacton seat in parliament.
It follows a series of scandals, including questions over a £5m donation from crypto-billionaire Christopher Harborne and his association with convicted criminal George Cottrell, who also gave him gifts.
He has been reported to the Electoral Commissioner and Parliamentary standards watchdog.
Here The Independent looks at who could replace him as Reform UK leader if he loses the by-election.
Richard Tice
The party’s multimillionaire deputy leader would be the most obvious choice to step up into the role.
He has led the party before, between 2021 and 2024, albeit when they were much less successful in the polls.
At the time he insisted the party could survive without Farage, and was not just a one man band.
He stood down to be succeeded by Mr Farage and in more recent years has been the party’s business spokesman.
Awkwardly, he was once described as a “pound-shop Nigel Farage” by one of the party’s current MPs, ex-Tory Lee Anderson, who eventually defected to Reform.
Robert Jenrick
The party’s Treasury spokesman is a former Tory leadership contender who joined Reform only this year, after he was dramatically sacked from the Conservative front bench and kicked out of the Tory party.
Kemi Badenoch took to social media to announce that she had fired Mr Jenrick after claiming to have seen “irrefutable evidence that he was plotting in secret to defect in a way designed to be as damaging as possible” to the Conservatives.
Hours later, as he joined Reform, Mr Jenrick launched an extraordinary attack on his former colleagues, saying the Tory party had “betrayed its voters and members” and was “in denial – or being dishonest” about its record.
Last year he accused Labour and Reform of being “locked in a bidding war to splash out more in handouts” when it came to the two-child benefits cap. He also once accused Farage of having “swanned off to Cheltenham to forget his troubles”.
As Treasury spokesman, he has also clashed with his new Reform colleague Zia Yusuf.
Zia Yusuf
A a self-described “proud British Muslim patriot”, last year Mr Yusuf dramatically quit his own party, using a social media post to say that trying to get Reform elected was not "a good use of my time".
But just two days later he was back, given the job of identifying “waste” in the councils the party now runs, inspired by Elon Musk’s role in Donald Trump’s White House.
Currently Reform’s spokesperson for home affairs, he publicly disagreed with Mr Jenrick over the details of the party's deportation policy last month.
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