Boris Johnson is widely regarded as favourite to be the UK’s next prime minister after Theresa May announced her resignation.

The former foreign secretary, who has confirmed he will stand in the Tory leadership race, has long eyed the job despite doubts among his party colleagues about his suitability.

If he moves into Downing Street, he will carry with him the baggage of a lengthy history of racially inflammatory remarks that could complicate international diplomacy.

Muslim women ‘letter boxes’ jibe

In an August 2018 column for the Daily Telegraph, Johnson wrote that women who wore the niqab looked like ”letter boxes” and “bank robbers”. He suggested it was “absolutely ridiculous” that people would choose to wear the “oppressive” religious headgear.

His comments infuriated other Tories and led Labour MP David Lammy to accuse him of “fanning the flames of Islamophobia to propel his grubby electoral ambitions”.

But the Conservative Party cleared him of breaching its code of conduct after an independent panel ruled his column was “respectful and tolerant”.

Picanninnies and ‘watermelon smiles’

In another Telegraph column, this one written in 2002, Johnson used two racial slurs to refer African people.

Tony Blair would love touring the continent, he wrote, because he will be greeted by “cheering crowds of flag-waving piccaninnies” – a racist term for a dark-skinned African child - and “the tribal warriors will all break out in watermelon smiles to see the big white chief”.

He apologised six years later during a London mayoral contest, though he claimed his words had been taken out of context.

Who could succeed Theresa May as Conservative leader? Show all 9 1 /9 Who could succeed Theresa May as Conservative leader? Who could succeed Theresa May as Conservative leader? Boris Johnson Former foreign secretary Boris Johnson has long been hopeful, he previously stood in the leadership contest that followed the Brexit vote and has at many times since been thought to be maneuvering himself towards the goal. He remains a darling of the party's right wing, particularly those in the ERG, and is the most popular choice among Tory voters but his leadership bid would be fiercely opposed by many MPs PA Who could succeed Theresa May as Conservative leader? Michael Gove Environment secretary Michael Gove is another member who has long wanted to be leader. He has lately been known for rousing his party in the commons, his recent speeches on the Brexit deal and Labour's no confidence motion have overshadowed the Prime Minister's. He has been loyal to the Prime Minister, partly to shed his reputation as a backstabber who abandoned Boris Johnson to stand against him in the 2016 leadership election Getty Who could succeed Theresa May as Conservative leader? Dominic Raab Former Brexit secretary Dominic Raab has emerged as a favourite to be the Brexiteer candidate in a contest to succeed to Ms May. He displayed a grip on detail in his role as Brexit secretary. When asked recently if he would like to become prime minister he replied "never say never" Getty Who could succeed Theresa May as Conservative leader? Rory Stewart International development secretary Rory Stewart is pitching himself as the sensible candidate, promising to rule out both a second referendum and a no-deal Brexit. He was only recently promoted to the cabinet, previously serving as prisons minister, where he caught headlines with a pledge to resign if he could not reduce levels of violence within a year PA Who could succeed Theresa May as Conservative leader? Esther McVey The former work and pensions secretary announced that she will be standing for the leadership when May leaves. McVey is the first to explicitly state that she intends to stand. She resigned from the cabinet in protest over May's Brexit deal AFP/Getty Who could succeed Theresa May as Conservative leader? Sajid Javid Home secretary Sajid Javid is said to have a plan in place for a leadership race. He made headlines over Christmas when he declared that people smuggling over the English channel was a "major incident" and more recently when he revoked the citizenship of ISIS bride Shamima Begum. Son of a bus driver, he wants the Conservatives to be seen as the party of social mobility PA Who could succeed Theresa May as Conservative leader? Jeremy Hunt Foreign secretary Jeremy Hunt was recently thought to be the favourite in the event of a leadership race as he could sell himself as the man to unite the party. Critics worry that his long stint as health secretary could return to haunt him at a general election. He has reportedly been holding meetings with Tory MPs over breakfast to promote his leadership PA Who could succeed Theresa May as Conservative leader? Andrea Leadsom Following the Prime Minister's second defeat over her Brexit deal, Leader of the house Andrea Leadsom hosted a dinner party at which "leadership was the only topic of conversation", The Times heard. Leadsom ran against Theresa May in the 2016 leadership election before dropping out, allowing May to become Prime Minister AFP/Getty Who could succeed Theresa May as Conservative leader? Priti Patel Former international development secretary Priti Patel is thought to be positioning herself as a contender. One MP told The Independent "she knows she's from the right of the party, the part which is going to choose the next leader, so she's reminding everyone she's there." Patel left the government late in 2017 after it emerged that she had held undisclosed meetings with Israeli officials PA

‘Part-Kenyan’ Obama

After Barack Obama intervened in Britain’s EU debate, Johnson suggested the then US president had an “ancestral dislike of the British empire” because he was “part-Kenyan”.

The remark led to him being accused of “dog whistle racism”.

Papua New Guinea 'cannibalism'

Johnson was again forced to apologise after he suggested the people of Papua New Guinea were cannibals.

Discussing party politics, he said in 2006: “For 10 years we in the Tory Party have become used to Papua New Guinea-style orgies of cannibalism and chief-killing, and so it is with a happy amazement that we watch as the madness engulfs the Labour Party.”

The Pacific nation's high commissioner in London did not see the funny side, and demanded an apology.

Support free-thinking journalism and attend Independent events

Colonialism 'the best fate for Africa'

Writing in The Spectator in 2012, Mr Johnson suggested that Africans would be better off if ruled by white colonisers.

He said: "Consider Uganda, pearl of Africa, as an example of the British record. The British planted coffee and cotton and tobacco, and they were broadly right. If left to their own devices, the natives would rely on nothing but the instant carbohydrate gratification of the plantain.