A senior UKIP MEP has resigned as party whip after an anti-Islam campaigner was cleared to stand in the leadership election.
Mike Hookem announced he was quitting as deputy whip in the European Parliament after chief whip, Stuart Agnew, declared his support for Anne Marie Waters.
Ms Waters has called Islam “evil” and set up the Sharia Watch pressure group.
She is one of 11 candidates who has been cleared to run in the leadership contest by the UKIP national executive committee.
Mr Hookem said he was not prepared to “turn a blind eye” to extremism.
In a statement, he said: “I strongly disagree with the views Ms Waters and Mr Agnew promote and I would like to put as much distance between me and them as possible.
“If I were to continue in my position of deputy whip, I would be seen as supporting or at the very least turning a blind eye to extreme views and this is not something I am prepared to do.
“I am not a racist and have never campaigned on race issues. While I do believe in controlled immigration, this position is about ‘space rather than race’; and I am not prepared to support someone who seeks to single out a section of our society simply due to their religious beliefs.”
Mr Hookem resigned after the party’s deputy leader Peter Whittle defended Ms Waters’ right to stand as a candidate.
Mr Whittle, who is also running for leadership, told the BBC Radio 4 Today programme: “The whole thing was done very rigorously.
“There was a vetting process. We all had to go through it and if you all get through that then you absolutely have the right to stand. That means Anne Marie should be able to stand.”
Mr Hookem said he was disturbed by comments by Mr Agnew that he “looks forward to telling his grandchildren in the future how he helped in the fight against Muslims”, and would keep a scrapbook of communications from those who disagreed.
In reference to his resignation letter, he said: “Let Agnew add this to his scrapbook!”
The party has been divided by Ms Waters’ candidacy with some members threatening to resign and former leader Nigel Farage has warned UKIP will be “finished” if it became an anti-Islam party.