A former UKIP politician who co-wrote the party’s 2019 manifesto has handed in his membership to run for Mayor of London as an independent.

David Kurten, who sits on the London Assembly as a Brexit Alliance Group member, says he offers a “unique” social conservative platform.

The controversial politician favours extremely limited immigration, advocating 10,000 net migrants a year to fill skills gaps.

He has previously suggested that homosexuality could be linked to childhood sexual abuse, and opposes LGBT sex education.

And he was criticised for “dehumanising” disabled people after referring to Remain voters as “retards”.

Mr Kurten told the Local Democracy Service he would fill a “political space” in the Mayoral race.

He said the politics of UKIP and the Brexit Party would need “rebranding” after Britain leaves the EU later this month.

Mr Kurten described Conservative candidate Shaun Bailey as a “great guy” but claimed he would be “less politically correct and less tied into strictures and rules from Number 10”.

The former UKIP education spokesperson said Brexit remained part of his mayoral platform.

He said: “I think London needs a Mayor that will appreciate the benefits of Brexit and the opportunities offered by our friend President Trump.”

Mr Kurten said he would have a “zero tolerance” approach to crime and stop-and-search should increase – regardless of the age of the suspect.

He said stop-and-search “isn’t pleasant” but “we have to do something”.

The former teacher also opposes the expansion of the Ultra Low Emission Zone, and said he would rip up the Cycle Super Highway between Blackfriars and Tower Hill.

He admitted toxic air pollution in the capital breaches legal limits, but said further action would be “devastating” for businesses.

Mr Kurten joins current Mayor Sadiq Khan, Conservative candidate Shaun Bailey, Liberal Democrat Siobhan Benita, Green Sian Berry and independent Rory Stewart in the race for City Hall.

Mr Khan had a comfortable lead in the latest poll, with 45 per cent of the vote, ahead of Shaun Bailey on 23 per cent.

Responding to Mr Kurten’s announcement, Ms Benita said she is “fighting for a safer, greener, kinder London”.

She said: “A pro-Brexit, pro-Trump, anti-diversity, socially conservative candidate won’t find much love in London.”

A spokesperson for Sadiq Khan said: “Sadiq is standing up for London’s values by leading the fight against Brexit, defending the rights of EU citizens in London, standing up to the anti-London Tory Government.”

Conservative Shaun Bailey, Green Sian Berry and independent candidate Rory Stewart were approached for comment.

The Mayoral election will take place on May 7.