A UKIP politician who once claimed that “a homosexual donkey raped my horse” announced his intention to seek his party’s leadership yesterday.

John Rees-Evans said he was standing for the top job because “significant changes to the culture of politics in Britain are long overdue.”

But the former parliamentary candidate immediately faced questions about embarrassing comments exclusively exposed by the Morning Star in December 2014.

Then standing in the Welsh valley seat of Cardiff South and Penarth, Mr Rees-Evans was one of a clutch of Ukip activists who confronted anti-racist protesters outside the party’s Merthyr Tydfil offices.

He was asked to explain comments made by other Ukip activists, including former Ukip branch chair Julia Gasper’s remark that “some homosexuals prefer sex with animals.”

Mr Rees-Evans responded: “Actually I’ve witnessed that … a homosexual donkey raped my horse.

“I was personally quite amazed, I’ve got a horse, it was in the fields … a donkey came up which is male and, I’m afraid, tried to rape my horse.”

When contacted by the Star at the time, Mr Rees-Evans defended the remarks, but said that “sexual relationships shouldn’t be policed … so long as there is consent.”

But he appeared to be frustrated when he was quizzed about the incident on BBC2’s Daily Politics programme yesterday.

“It was a bit of playful banter with a mischievous activist,” he said. “I’m sorry if I offended anyone in doing that.

“I concede it was a mistake to be playful with an activist in a street. The fact is I’m not a politician. The guy was just asking me questions in the street. It was an error of judgement.”

Mr Rees-Evans, an ex-soldier who migrated to Bulgaria but says he moved back to Wales before last year’s general election, also disputed reports he carried a handgun in Ikea to fend off terrorists.

A Vice News article also reported that his planned “fortress” in the country would incorporate a church, a leisure complex, an underground bunker, a firing range, and a panic room and a watchtower.

But the Ukip man said yesterday the article consisted of “exaggerated journalism.”

His opponents in the race include MEP Suzanne Evans, deputy leader Paul Nuttall and “alt-right” activist Raheem Kassam.

Earlier this year, Mr Kassam tweeted: “Can someone just like … tape Nicola Sturgeon’s mouth shut? And her legs, so she can’t reproduce. Thanks.”