UKIP Deputy Leader, Margot Parker MEP, resigns over Henry Bolton and has called for him to step down as leader.
The resignation came after UKIPs National Executive Committee voted in favour of a motion of no confidence in him.
Mr Bolton has left the party in “limbo” and he should go “sooner rather than later”, she told BBC Radio Northampton.
The party’s immigration spokesman, John Bickley, has also now quit his role. Mr Bolton has been under fire over texts sent by his former girlfriend.
Ms Parker, who is also an East Midlands MEP, said Mr Bolton’s “personal life took over the job he was elected to do”.
She added: “It would be quicker and cleaner if he came to the conclusion he could go sooner rather than later.
“This is taking time away from doing the job. This puts the party in a limbo situation.”