Rory Stewart quits Boris Johnson's Conservative party and announces that he will stand to be mayor of London as an independent candidate.

The MP said he would stand to become the capital's next mayor to counter the 'extremism' taking over British politics.

He said it was with 'sadness' that he was quitting the party.

Stewart was the surprise package in the race to replace Theresa May as Conservative party leader and prime minister this year.

However, he is a staunch opponent of a no-deal Brexit and had the Conservative whip removed from him after voting to prevent a no-deal exit last month.

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LONDON — Rory Stewart has resigned from Boris Johnson's Conservative party and said he will stand to be the next mayor of London as an independent candidate.

Stewart, who ran against Johnson in the contest to replace Theresa May as party leader and prime minister earlier this year, said on Friday morning that he was quitting the Conservative party with "sadness."

Shortly after, he announced that he was quitting Westminster politics and standing as an independent candidate in London's next mayoral election.

Stewart will go up against the Labour Party's current London mayor Sadiq Khan, Conservative candidate Shaun Bailey, and the Liberal Democrats' Siobhan Benita, when the capital goes to the polls in 2020.

Writing for London's Evening Standard newspaper, Stewart said: "Our leaders have become so bad at listening to the people... Instead, they have retreated to a madhouse of mutual insults in the Gothic shouting chamber of Westminster, pitting one group against another — rich against poor, London against the rest, Brexit against Remain — and all the time getting further and further away from compromise, practical solutions, and the centre-ground.

"And this is why I've decided to stand, not for a party, but as an independent."

In a tweet announcing his campaign to be London mayor, he said the capital "is a city not just with so much potential but of course a city that is now in real danger — danger from Brexit, from technological change, but I think above all, from what's happened to British politics, to the kind of extremism that is taking over our country."

Stewart quits the Conservative party after a rollercoaster year

Stewart had in recent months become increasingly at odds with the Conservative party's pro-Brexit membership over his staunch opposition to a no-deal exit from the European Union.

Last month, he and 20 other MPs had the Conservative whip removed after they voted to prevent a no-deal Brexit.

On Friday morning he tweeted: "It's been a great privilege to serve Penrith and The Border for the last ten years, so it is with sadness that I am announcing that I will be standing down at the next election, and that I have also resigned from the Conservative Party."

Stewart is not the only MP to have quit the Conservative party in recent weeks.

Amber Rudd, a leading Conservative moderate, stood down as Work & Pensions Secretary in September and resigned the party whip, in the same week as Jo Johnson, the prime minister's own brother, said he would be resigning as a minister and standing down at the next election, having previously voiced opposition to a hard Brexit.

Anna Soubry, Heidi Allen, and Sarah Wollaston, and Sam Gyimah all defected from the Conservatives earlier this year for similar reasons. All four now represent other parties in the House of Commons.

Who is Rory Stewart?

Rory Stewart Getty

Stewart was elected MP for Penrith and The Border in 2010.

He served as Secretary of State for International Development in 2019 in Theresa May's government but rose to prominence when he entered the contest to replace the former prime minister.

He started the race as a little-known outsider and was not seen as a leading candidate.

However, his campaign quickly gathered momentum and national attention, impressing both Conservative MPs and the general public with his strategy of travelling around the country and speaking directly with people.

Stewart used the Twitter hashtag #RoryWalks while touring the country as a leadership candidate.

During his campaign, Stewart was highly critical of Johnson.

At one rally he questioned whether the current prime minister could be trusted with national security.

"I don't want to make this too personal — do you really feel that this is the person that you want engaging with the detail and the future of your health and education system?" he said.

"Is this the person that you want writing the instructions to the nuclear submarines?

"Is this the person that you want embodying the nation on the world stage and guiding you through the most difficult choice that Britain has faced for 50 years?"