BORIS Johnson today hit out at "the doubters, the doomsters, the gloomsters" who believe Brexit is destined for failure as he finally became Prime Minister.
The new Tory leader met the Queen to start his time in office - and then headed to Downing Street where girlfriend Carrie Symonds watched on as he made his tub-thumping first speech.
Speaking outside No10, BoJo blasted: "The doubters, the doomsters, the gloomsters - they are going to get it wrong again. The people who bet against Britain are going to lose their shirts because we are going to restore trust in our democracy.
"We will do a new deal, a better deal that will maximise the opportunities of Brexit while allowing us to develop a new and exciting partnership with the rest of Europe.
"I have every confidence that in 99 days' time we will have cracked it."
Mr Johnson vowed to take personal responsibility for Brexit talks and the domestic agenda as he struck a patriotic tone in his debut speech.
He joked: "Never mind the backstop, the buck stops here!"
Over the coming hours the Prime Minister will begin to announce who will be in his Cabinet with Leave veterans replacing a string of departing Remainers.
In a shock move, Defence Secretary Penny Mordaunt - a staunch Brexiteer - was sacked along with fellow ministers Liam Fox and Greg Clark.
On the day of a historic handover of power:
- The new PM appointed a top table of leading Brexiteers
- He promised to fix social care, hire 20,000 cops and slash taxes
- BoJo also said he would upgrade 20 hospitals, cut GP waiting times and boost spending on schools
- Four pro-Remain ministers quit rather than serve under Boris
- Theresa May made an emotional final speech outside No10
Mr Johnson, 55, is the 14th Prime Minister to have served under the current Queen - and the third PM since the Brexit referendum which still hasn't been delivered.
He is also the first unmarried leader of the country for 45 years, and is the 20th Prime Minister to have been educated at Eton.
The last one, BoJo schoolmate David Cameron, today welcomed him to the job saying: "I wish you well."
This afternoon the new PM pledged: "My job is to serve you the people - because if there is one point we politicians need to remember it is that the people are our bosses."
The people who bet against Britain are going to lose their shirts
Boris Johnson
The PM repeated his vow to take Britain out of the EU on October 31 "no ifs, no buts" and warned the EU that a No Deal outcome would be their fault if they refused to negotiate a better Brexit deal.
He also extended the hand of friendship to Europeans living in Britain, promising to protect their rights no matter what happens with our EU exit.
Mr Johnson started by praising Mrs May, who formally resigned minutes before he took office.
He said: "I pay tribute to the fortitude and patience of my predecessor and her deep sense of public service.
"But in spite of all her efforts it has become clear that there are pessimists at home and abroad who think that after three years of indecision that this country has become a prisoner to the old arguments of 2016, and that in this home of democracy we are incapable of honouring a basic democratic mandate."
Insisting that post-Brexit Britain will thrive even in a No Deal scenario, he added: "I say do not underestimate this country!
"Do not underestimate our powers of organisation and our determination because we know the enormous strengths of this economy in life sciences, in tech, in academia, in music, the arts, culture, financial services.
"It is here in Britain that we are using gene therapy, for the first time, to treat the most common form of blindness. Here in Britain that we are leading the world in the battery technology that will help cut CO2 and tackle climate change, and produce green jobs for the next generation.
"And as we prepare for a post-Brexit future it is time we looked not at the risks but at the opportunities that are upon us."
In a final blast, Boris said: "At this extraordinary moment in our history and after three years of unfounded self-doubt it is time to change the record.
"No one in the last few centuries has succeeded in betting against the pluck and nerve and ambition of this country. They will not succeed today.
"We in this government will work flat out to give this country the leadership it deserves, and that work begins now."
Boris arrived at Buckingham Palace to become Prime Minister at 3.10pm minutes after Theresa May officially resigned.
Shortly afterwards, Royal officials released a picture of the new PM bowing to Her Majesty as she formally asked him to form a new Government.
He was not accompanied by Miss Symonds, 31, for his meeting with the Queen, but she watched the speech outside No10 with his top aides.
Her position alongside chief of staff Eddie Lister suggests she will play a key role in the new Government.
The Sun Says
BORIS Johnson’s sensational first speech at No10 looks a game-changer for Britain.
It was delivered at such a breakneck pace, so packed with detail and infused with such energy, optimism and national pride that we defy anyone bar the most bitter Remoaners not to feel inspired.
There was virtually no aspect of our lives Boris claimed his Government would not improve.
We can all be cynical about how much he will actually achieve, with Brexit still paramount and his Commons majority near non-existent. But what a hurricane blast of fresh air it was after three years of grim defeatism and paralysis.
In 11 minutes we learned about Boris’s “new deal” Brexit and Boris’s Britain — where no town is left behind, where the strength and ingenuity of our people conquer all adversity and in which 3.2million EU migrants are welcome to stay.
There will be 20,000 more police, 20 hospital upgrades, a new social care plan and more cash for schools.
The EU, like our new PM’s many detractors, can scoff all they like.
They can resolve to be as stubbornly destructive as they have since 2016.
But on the strength of that opening salvo Boris is very likely to have the people behind him in a way Theresa May did not.
And he is setting Brussels up, rightly, for the blame if we are “forced out with No Deal”. Eurocrats simply can no longer insist on shackling us to an Irish backstop that keeps us tied to them.
Remainers are keen to paint Boris as the “British Trump”. It is a myopic error. Not least because this speech had such depth, intelligence and oratorical skill.
It was a brilliant debut. But today the challenge Boris has longed for his whole life truly begins.
A spokesman for the Royal Family said this afternoon: "The Queen received in Audience The Right Honourable Boris Johnson MP this afternoon and requested him to form a new Administration.
"Mr Johnson accepted Her Majesty's offer and kissed hands upon his appointment as Prime Minister and First Lord of the Treasury."
A group of Greenpeace protesters tried to block BoJo's path to power by forming a human chain across the Mall to stop his convoy's route to the Palace.
Police had to shove the activists out of the way to allow the new Prime Minister to keep his appointment with the Queen.
His first act on entering No10 will be to write letters to the commanding officers of Britain's nuclear submarines.
The notes will instruct them on what to do in the event of a successful nuclear strike on the UK.
QUEEN'S JOKE ON ROLE
THE Queen meets BoJo in Buckingham Palace — hours before he made his first indiscretion as PM by revealing what she said.
As he toured No 10, where he was applauded by staff, he let slip that Her Maj joked: “I don’t know why anyone would want the job.”
The background of the royal snap shows engagement portraits of Wills and Kate plus Harry and Meghan — and a £550 Dyson Pure Hot+Cool Link purifier fan to keep the room cool.
He will then start making appointments to his Cabinet, with several top jobs expected to be filled by the end of the day.
Within minutes of Mr Johnson entering No10, Ms Mordaunt revealed she was being fired after less than three months as Defence Secretary.
Liam Fox was also sacked by the new PM sparking speculation he is purging high-profile supporters of leadership rival Jeremy Hunt. Greg Clark and Chris Grayling are leaving the Government too.
This morning, Mr Johnson made a bid to shore up his Brexiteer credentials with the appointment of Vote Leave boss Dominic Cummings as a senior advisor.
The eccentric campaigner was central to delivering the Leave vote in 2016 and could be a sign Boris intends to take a tough line in talks with the EU.
Brussels boss Donald Tusk warned the new PM he would need a grasp of the "detail" as negotiations reopen.
He's expected to appoint top Brexiteer MPs to his Cabinet over the next 24 hours with Priti Patel and Dominic Raab set for senior jobs.
But in a potential sign of trouble, four senior ministers including Mrs May's deputy said they wouldn't serve under the new Prime Minister and vowed to fight any attempt to deliver a No Deal Brexit.
Philip Hammond and David Gauke fulfilled their promise to resign formally even before Mr Johnson took office while David Lidington, the Chancellor of the Duchy of Lancaster, announced he would be headed to the back benches.
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He warned: "After more than two decades of collective responsibility I'm now relishing the prospect of speaking and campaigning freely for the things that matter to me and to my constituents."
Rory Stewart is also stepping down and could lead the Tory rebels determined to wreck the PM's Brexit plans.
In her final speech outside No10, Mrs May sent a signal to Mr Johnson not to try and take Britain out of the EU without a deal - but added he would have her "full support" after taking over from her.
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