The chairman of UKIP is to step down after overseeing next Saturday’s vote on the future of leader Henry Bolton.
Paul Oakden said he had intended to step down last autumn, but agreed to stay on for a short time at Mr Bolton’s request after his election.
UKIP members will decide whether to back or sack Mr Bolton following criticisms of his private life.
Mr Oakden said he had “absolute faith” in members to do what was right to protect the party’s long-term future.
Mr Bolton lost a vote of confidence by the party’s national executive committee last month after it emerged that his partner, Jo Marney, had sent offensive texts about Meghan Markle, who is to marry Prince Harry in May.
Analysis: Won’t help infighting image
By BBC political correspondent Alex Forsyth
Paul Oakden has remained in his post through one of UKIP’s most tumultuous periods.
He’s overseen the appointment of the succession of leaders that followed Nigel Farage’s departure; each promising to restore unity, yet unable to end the infighting.
He’s been rolled out to face the cameras in the aftermath of Diane James’ short-lived tenure, then Paul Nuttall’s decision to depart, and most recently the questions over Henry Bolton’s future.
Mr Oakden has defended the party in the face of those who claimed it had lost its purpose and direction, critics who said it was failing financially and claims it had haemorrhaged members.
Throughout, he maintained his belief in UKIP’s place on the political playing field.
Even now, Mr Oakden has been clear his departure is not a reflection on the party’s current woes; he says he will remain a committed member of UKIP.
Nonetheless, his decision to resign as chairman won’t help the image of a party fighting for stability amid continued turmoil.
Mr Bolton’s political fate will now be decided by the party’s members at an extraordinary general meeting in Birmingham.
Speaking on Sunday, Mr Bolton suggested he was still in a relationship with Ms Marney and rejected suggestions his leadership was over, despite a wave of resignations from his frontbench team in recent weeks.
In a letter to UKIP supporters, Mr Oakden said now was the “right time” to go.
But he insisted it had nothing to do with next Saturday’s vote, saying he was required to remain “impartial” in the leadership process and would continue to serve the party.
“I have made this decision irrespective of the outcome of the EGM and I’m announcing it now to ensure that it remains absolutely unconnected to whatever democratic decision the membership may take on Saturday,” he said.
Mr Bolton, UKIP’s fourth party leader in about 18 months, has suggested he will overhaul the NEC if he wins Saturday’s vote, as part of efforts to professionalise the party.