A Ukip parliamentary candidate standing in Wales has claimed a “homosexual donkey” tried to rape his horse.

John Rees-Evans, who is running for Cardiff South and Penarth in May’s general election, told the bizarre story to protesters outside a new campaign office in Merthyr Tydfil.

An anti-Ukip demonstrator had asked him to respond to a string of controversial quotes by fellow party members, including on from Dr Julia Gasper in Oxford, who allegedly claimed that “some homosexuals prefer sex with animals”.

“Actually, I’ve witnessed that,” Mr Rees-Evans responded. “I’ve got a horse and it was there in the field. And a donkey came up…which was male, and I’m afraid tried to rape my horse.”

The stallion bit the “homosexual donkey” in defence, the former soldier continued, saying he leapt to the animal’s defence and hit the horse to protect it.

“I don’t think that’s what she meant but it’s a coincidence,” he added.

Mr Rees-Evans’ comments came after the chairman of Ukip, Steve Crowther, urged members not to join Facebook or Twitter to avoid gaffes.

“My advice: just don’t,” he wrote in the party’s official magazine.

Footage of the interview on Saturday was uploaded on YouTube, showing protesters in the background voicing their opposition to Ukip’s latest office.

Harriet Protheroe-Davis, who organised the demonstration, told the Morning Star that they were making a stand about Ukip’s “overall ideology”.

“Comments like these from Ukip councillors are exactly why we held our demonstration,” she added.

In pictures: The rise of Ukip Show all 8 1 /8 In pictures: The rise of Ukip In pictures: The rise of Ukip 1993: Alan Sked forms Ukip History professor Alan Sked had been active in anti-EU politics for a while beore he founded Ukip in 1993. He resigned from the party after the 1997 election, concerned that it was attracting far-right members, and has been critical of Ukip since. Picture: Reuters Reuters In pictures: The rise of Ukip 2005: Kilroy defects Former TV presenter Robert Kilroy-Silk founded Veritas in 2005, after a failed bid to become leader, and took many of Ukip's elected members with him. But the party slowly lost its popularity and didn't put forward any candidates in the last election. Picture: REUTERS/Kieran Doherty REUTERS KD/RUS In pictures: The rise of Ukip 2010: Farage becomes leader, again Farage had led Ukip from 2006 until 2009, when he stood down to fight against the Speaker, John Bercow, for his Buckingham seat. He failed to win the election and returned to lead the party in November 2010. Picture: REUTERS/Kieran Doherty REUTERS/Kieran Doherty In pictures: The rise of Ukip 2010: Ukip fights for election Nigel Farage was injured in a plane crash on polling day in the 2010 general election, but his party increased its success in the votes. It fielded 572 candidates and took 3.1% of the vote, though failed to win any seats. REUTERS/Darren Staples REUTERS/Darren Staples In pictures: The rise of Ukip 2013: Eastleigh gains Ukip's candidate Diane James got the highest ever number of votes for any candidate from the party, but was beaten by the Liberal Democrats. The surge in support gave Ukip confidence ahead of local and European elections later in the year. Picture: Reuters In pictures: The rise of Ukip 2013: Bloom kicked out Godfrey Bloom, who served as an Ukip MEP from 2004 to 2014, had the whip withdrawn in 2013 after sexist comments and an attack on a journalist. He sat as an independent MEP until 2014, when he ended his term in office. Picture: REUTERS/Luke MacGregor In pictures: The rise of Ukip 2014: European election success Ukip got a higher proportion of the vote than any other party in 2014's European elections, adding 11 new MEPs and taking its total to 24. REUTERS/Luke MacGregor In pictures: The rise of Ukip 2014: Carswell defects Douglas Carswell defected from Ukip at the end of August, and was followed by Mark Reckless at the end of September, who resigned from the Tories amid rumours of many more defections to come. Picture: REUTERS/Toby Melville

Mr Rees-Evans told The Independent he was a libertarian and was in “no position to declare that one particular form of sexual appetite is any more legitimate than any other”.

“My own background is quite traditional,” he added. “For me, any kind of non-conventional relationship that people have, I would say I don’t really understand the attraction, but we are a libertarian party.

“People can do pretty much anything they like in the privacy of their own homes as long as it doesn’t affect other people.”

The 36-year-old, who is married with three children, runs a mountaineering company based in Cardiff, holds the British Mens’ Kilimanjaro speed record and has lived in Tanzania, Uganda and South Africa.

The family returned to Britain last year and settled in Cardiff Bay. Mr Rees-Evans said he joined Ukip in September and requested the Cardiff South and Penarth because of family links to the area.