Boris Johnson news - live: Williamson, Raab and Patel return to government as new PM continues biggest cabinet reshuffle in modern history
Follow all the latest updates from Westminster
Allies of Ms May were unceremoniously cleared out, with rival Jeremy Hunt was among the senior figures to leave the government in favour of Brexiteers.
Sajid Javid was appointed as chancellor, with Brexiteers Priti Patel and Dominic Raab returning to the cabinet as home secretary and foreign secretary.
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Welcome to The Independent's politics liveblog - today Boris Johnson will enter Downing Street, replacing Theresa May as prime minister.
He is expected to launch a bid to broaden his appeal by using his first day in office to appoint women and ethnic minority MPs to what aides were terming a “cabinet for modern Britain”.
The shake-up is expected to include a return to the cabinet for Priti Patel, 20 months after she was forced to resign after she was revealed to have set up secret back-channel negotiations with the Israeli government, as well as promotions for rising stars from across different wings of the party.
After his landslide victory in the Tory leadership race, Mr Johnson faces an urgent need to shore up the party’s position, with his wafer-thin working majority expected to be reduced to just one after next week’s Brecon and Radnorshire by-election.
Responding to US President Donald Trump's statement that Mr Johnson and Brexit Party leader Nigel Farage would work well together, Mr Hancock told the BBC: "There is no way that we are going to have any kind of electoral pact with the Brexit Party and with Nigel Farage."
Writing in the Daily Telegraph today, Mr Farage claims: "[Mr Johnson] is going to have to risk his longed-for position as PM to ensure Brexit is enacted properly."
He continued: "The inescapable truth, therefore, is that he must hold an autumn general election. That is his only way out .. [and] for this strategy to work, he will need the support of the Brexit Party.
"If he is able to convince us, then together we would electorally smash the Labour Party, he would assume a big working majority, and he would go down as one of the great leaders in British history."
Boris Johnson last night appointed one of Sky’s senior executives as his business adviser, just days after it emerged the multi-millionaire had lent his £9.5m Westminster flat to the incoming prime minister.
As the newly-appointed Tory leader prepared to unveil his top team on Wednesday, it emerged Andrew Griffith, a chief finance director at the broadcaster, will enter Downing Street with Mr Johnson.
Labour immediately seized on the appointment, saying: “The public would be forgiven for coming to the conclusion that Johnson’s friends can buy influence with the new administration.”
Ian Blackford, the SNP leader at Westminster, told the BBC Radio 4's Today programme: "I think as it stands today he could be the last prime minister of the United Kingdom".
His warning echoes that of the former Labour prime minister Gordon Brown. who warned last week of an approaching "head on conflict" between the ex-foreign secretary's hardline views and the SNP's "extreme nationalism".
A key Boris Johnson supporter has stamped on Nigel Farage’s offer of a possible electoral pact to deliver a no-deal Brexit, insisting it will never happen.
The Brexit Party leader has renewed his suggestion of an alliance if the new prime minister calls a general election, to ensure the Commons has a majority for crashing out of the EU.
It could see the Brexit Party agree not to stand against Tory candidates committed to a no-deal, in return for the Conservatives giving Mr Farage’s party a clear run in Labour-held seats.
Europe's newspapers reacted with a mixture of disbelief, mockery, and depression at the news that Boris Johnson is to become British prime minister.
In a strident editorial the Irish Times refers to Mr Johnson's victory as "a new nadir" for the UK. The newspaper warned that the best hope for Ireland, Europe and "British citizens themselves - is that Johnson as prime minister will be guided by three of his worst traits, which together have defined his career: he doesn't mean a word he says, he is obsessed with power and he is willing to betray those closest to him in the pursuit of that power".
Over the North Sea, leading Danish broadsheet Politiken ran a leader column claiming that like US president Donald Trump, Mr Johnson has "built his entire career on shameless lies and extreme self-promotion".
Dominic Cummings is set to be appointed an adviser to Boris Johnson, despite being found in contempt of parliament over an inquiry into “foreign influence and voter manipulation” in the Brexit vote.
The new prime minister is expected to take the hugely controversial step of inviting the head of the Vote Leave campaign – and the brains behind the notorious “£350m-a-week for the NHS” claim – into No 10.
The move was immediately condemned by Sarah Wollaston, a former Conservative, now Independent, MP as “shameful”.
Sir Mick Davies, a treasurer and chief executive at Conservative Party Headquarters, has resigned from his position before Boris Johnson enters Downing Street.
In a letter, posted on the Conservative Home website, he says: "I have so much enjoyed my time as Treasurer and CEO, but circumstances change and I think that our new leader, Boris Johnson, should be free to choose a team at CCHQ who can work together to ensure that this organisation realises its central purpose – a clear and decisive victory at the next General Election."
The letter - addressed to Tory donors - adds: "I am writing to ask you to get behind our new leader, Boris Johnson, and make sure CCHQ can deliver. Good politics is not a cheap exercise and if we are not properly resourced and financed we will risk a very bad outcome – Jeremy Corbyn in Number 10.
"You all know that one of my great bugbears has been the lack of unity in our party. Divided parties do not win elections. Brexit with all its complexities and associated dogmas provides the unfortunate backdrop for division but if we are to effectively stand against the frightening threat of a Corbyn led Labour Government we all must find a basis of coming together.
"Our new leader and prime minister can only be effective if a strong and unified party stands behind him. One of the key roles of CCHQ is to facilitate that outcome but I am asking you our donors, upon whom we depend, to embrace that call for unity as well. There is today no room for bystanders – my successor will need your help and I hope that you will step forward right now and send a powerful message of unity, purpose and commitment."
"Theresa May tried hard to have a meaty domestic agenda beyond Brexit but ultimately failed," writes The Independent's political commentator Andrew Grice. "Brexit consumed the government machine and left little bandwidth for much else."
He adds: "Boris Johnson will try to learn from her mistakes – and his own very obvious lack of a plan on the morning after the 2016 referendum after leading the Vote Leave campaign to an expected victory."
Here are six urgent priorities beyond Brexit on which Prime Minister Johnson needs to make his mark ––