Nigel Farage has said 10 Reform councillors who quit in protest over his "autocratic" leadership were put forward by a "rogue branch" of the party.
The Derbyshire group made the announcement after billionaire X owner Elon Musk said Mr Farage "doesn't have what it takes" to lead the party.
The Clacton MP told Sky News he is still friends with Mr Musk and insisted he "can't be pushed or bullied" by anybody.
The group of councillors said in a statement Reform was being run "in an increasingly autocratic manner" and it had lost its sense of direction.
But Mr Farage told BBC Newsnight that none of the councillors who quit ahead of Reform's South East of England Conference - one of a series of regional events aimed at building up the party's support base - had "passed vetting".
"We had a rogue branch putting people up and I think you'll find, in many cases, there will have to be by-elections because they were not legitimately put forward," he said.
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The statement from the Amber Valley group criticised Reform's focus on recruiting former Tory councillors rather than the grassroots.
"This shift away from the party's founding principles and values has caused deep concern," it said.
Zia Yusuf, the chairman of Reform UK, said on X that the rebel group's leader Alex Stevenson had been suspended for nominating candidates that failed vetting in December.
He said many of those who had resigned alongside Mr Stevenson were effectively "illegitimate" and new elections must be held.
Mr Stevenson confirmed to Sky News he had been suspended and said it was due to an internal fight within the party.
The row may cause trouble for Mr Farage as he targets gains in the local elections in May.
(c) Sky News 2025: Nigel Farage hits back at 'rogue branch' after 10 Reform councillors quit in pro
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