UKIP’s ruling national executive committee (NEC) has unanimously backed a vote of no confidence in party leader Henry Bolton.
Mr Bolton has faced repeated calls to quit over offensive texts sent by his former girlfriend.
But he has said he will defy the committee and continue as leader, as a contest would finish the party.
The committee does not have the power to remove him – that can only be done by a vote of the party’s membership.
UKIP chairman Paul Oaken said Mr Bolton was “disappointed” by the NEC’s decision but understood “that the party has a process to through”.
“Henry was offered the opportunity to resign but he has made clear that he feels he is the right man to lead the party forward,” he added, after a three hour emergency meeting to decide his future.
Mr Bolton had earlier toured TV and radio studios, saying the committee had no right to pass “moral” judgement on his private life.
He said he had ended the “romantic element” of his relationship with girlfriend Jo Marney after she sent texts saying Prince Harry’s fiancee Meghan Markle would “taint” the Royal Family.
But he said he would “support her in rebuilding her life”, which he said had been “turned on its head”.
If the former army officer were to step down it would leave UKIP seeking its fifth leader in 18 months.
He warned that another leadership contest could spell the end for the party, which is believed to be heavily in debt, and calls for his resignation were part of a “coup” attempt by a rival faction in the party.
“If the NEC decides to go down the road of months of further in-fighting and further negative media scrutiny by deciding to pass a vote of no confidence in me I think that the reality is that the party is probably over,” he told ITV’s Peston on Sunday.
He said the NEC should be focusing on ensuring the party’s “survival” rather than discussing his leadership.
Membership to vote
After a discussion of “recent press coverage” of the leader, “the committee took the decision to hold a vote of no confidence in the leadership of Henry Bolton, UKIP said in a statement.
“The vote was carried unanimously with the exception of the leader.
“This decision will automatically trigger an Emergency General Meeting of the party, to allow the membership of UKIP the democratic opportunity to decide to endorse or reject that vote of no confidence.”