A gay former UKIP member has resigned from the party in protest at the selection of a candidate, who once compared gay rights campaigners with Nazis, to run in this May's London Assembly election.

Alan Craig, who was also invited to speak at a 'gay cure' conference last year, is UKIP's choice to stand in the south west London constituency, covering Hounslow , Kingston and Richmond .

He was chosen at a hustings on Friday, February 5, ahead of the prominent LGBT (lesbian, gay, bisexual and transgender) campaigner Richard Hendron.

Mr Hendron, who stood for UKIP in Brentford & Isleworth at the 2015 General Election, said Mr Craig's selection meant he "could simply not defend the party anymore".

In an open resignation letter to UKIP chairman Steven Crowther, the barrister and former police officer said it was the "straw that broke the camel's back" after being subjected to "vile homophobic abuse" from within the party.

Alan Craig, UKIP candidate for London Assembly south west constituency

Mr Craig has defended himself, insisting he is not homophobic, respects the rights of LGBT people and has never advocated the idea of a 'gay cure'.

In his resignation letter, Mr Hendron wrote: "Since raising my head above the parapet promoting LGBT issues in UKIP, trying to improve things for UKIP and the LGBT community, I have received the most vile homophobic abuse, witnessed intolerance like I have never seen before and been subject to a hate campaign.

"Senior UKIP officials have not only failed to act, support and intervene, but have also been the perpetrators."

'Vile homophobic abuse'

He went on to say: "There is no other way to describe Alan Craig other than a vile, nasty homophobic individual who is driven by hatred of the LGBT community."

Mr Hendron claimed Mr Craig's selection was the culmination of active efforts by the party's local hierarchy to prevent an outspoken supporter of gay rights from standing.

The party had lost his applications on five previous occasions, he said, and he only found out about the hustings on the afternoon it was due to take place.

In an article in 2011, Mr Craig compared gay rights campaigners to Nazis, describing them as the 'Gaystapo' in an attack on gay marriage.

In April 2015, the former Christian Peoples Alliance leader was invited to address a conference in Westminster called Transformation Potential: Unwanted Same-Sex Attractions: Is Change Possible? The event was criticised by gay rights campaigners, who said it advocated the idea of a 'gay cure'.

Mr Craig was listed as part of a panel discussing the topic 'Raising awareness; resisting indoctrination; supporting campaigns to secure freedoms and rights for children, counselees, therapists and pastors'.

Mr Craig insisted he was not homophobic and respected the rights of LGBT people.

'I am not homophobic'

He told getwestlondon he was asked to speak at last year's Transformation Potential conference on the subject of gay politics and did not believe homosexuality was an affliction which could be 'cured', nor had he ever expressed such a view.

He said the term 'Gaystapo' was a pejorative term coined by the gay journalist Johann Hari which he had borrowed to describe the politics of some gay activists.

"I am not homophobic. LGBT people deserve respect and the right fully and freely to pursue their lives within the law like every other citizen," he said.

"Further, in a democracy like ours where there is free speech, LGBT activists are free publicly to criticise my politics in the same way as I am free to criticise theirs."

Asked whether he thought his outspoken views might deter the LGBT community from voting for UKIP, he said: "I hope not. I actively support Peter Whittle, UKIP's gay candidate for London Mayor.

"I genuinely like most gay people I am involved with at work or socially and have nothing against them personally.

"I reserve the right to criticise the political agenda of some gay activists, in the same way as I criticise the political agendas of other people."

Petition seeking Alan Craig's removal from list of candidates

A petition seeking the removal of Mr Craig from UKIP's approved candidates list has been started on the website Change.

The petition, which had more than 125 signatures within 24 hours of being set up by Richard Hilton, said: "While we support Mr Craig's right to free speech, we believe it is inappropriate for UKIP to appear to endorse his offensive views by approving him as a GLA candidate.

"His appointment undermines the work of hard-working gay candidates like London Mayoral candidate Peter Whittle and others. We call on the UKIP Leader Nigel Farage and the NEC to urgently review Mr Craig's suitability as a candidate."

getwestlondon has approached UKIP for a comment.