The candidate for Reform UK - formerly the Brexit Party - is also the founder of the Fair Fuel UK campaign, lobbying to freeze fuel tax and keep petrol prices down.

Here, Sky News looks at Mr Cox's career and campaigning priorities as he makes his bid to "ditch Khan" from City Hall.

Party: Reform UK
Campaigning priorities: Scrap ULEZ in its entirety, cut crime and build houses
Notable achievements: Founder of Fair Fuel UK

Mr Cox calls himself a "lifelong Conservative voter" who felt compelled to run for Reform UK because "a vote for the Tories is a vote for Labour's Sadiq Khan".

He has spent the last decade campaigning through Fair Fuel UK for fuel duty to be frozen. He claims the group has "stopped £200bn in tax hikes".

Mr Cox has voiced scepticism about climate change, tweeting last year that "there is no climate crisis" and saying he was "convinced man is not responsible for global warming".

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However, he told the Evening Standard it was "unfair" for him to be labelled a "climate change denier", saying he believed the climate was changing but did not think it was a "crisis".

Mr Cox runs a business development consultancy firm for UK small and medium-sized enterprises (SMEs) and is a fellow of the Institute for Independent Business, a network supporting owners of independent businesses.

Campaigning priorities

Mr Cox wants to do away with ULEZ completely - not just halt the expansion to Greater London, as other candidates are seeking.

His vision of getting the city moving also involves scrapping low traffic neighbourhoods and 20mph zones.

He wants to incentivise drivers to adopt clean fuel technology but said this should be done without using "cash-grabbing restrictive policies".

He promised to increase police visibility to cut crime and "massively increase" the number of affordable homes in the capital.

Mr Cox also wants to make sure 5G and reliable wi-fi are available throughout the city.