Following Mr Johnson's victory, polling company YouGov asked members of the public what they thought of the news, and whether there should now be a general election.

BBC Radio 5 Live

Image source, Reuters

BBC Radio 5 Live's Emma Barnett was broadcasting live from College Green outside the Houses of Parliament as Boris Johnson was elected leader of the Conservative Party.

Emma spoke to Conservative MPs, party members and 5 Live listeners across the UK, to get their reaction.

Click here to listen to the highlights on BBC Sounds.

Image source, Parliament TV

MP for the Sherwood constituency in Nottinghamshire since 2010, Mark Spencer has been a government whip under Theresa May since 2016.

He studied at Shuttleworth Agricultural College before joining the family farm business, and also served as chairman of the National Federation of Young Farmers’ Clubs.

Previously a county councillor, he won his seat in 2010 with the slender majority of 214, but it now stands at 5,198 after the general election in 2017.

He advocated Remain during the 2016 Brexit referendum campaign.

Image source, Getty Images

DUP leader Arlene Foster has confirmed her party's confidence and supply deal with the Conservative Party will undergo a scheduled review under new leader Boris Johnson - but remains in place for now.

"I have spoken with Boris Johnson and congratulated him on becoming leader of the Conservative Party," she said.

"We discussed our shared objectives of strengthening every part of the Union, ensuring the 2016 referendum result is implemented and seeing devolution restored in Northern Ireland.

"The confidence and supply agreement between the Conservative Party and the Democratic Unionist Party remains.

"That agreement included a review between each parliamentary session. This will take place over the coming weeks and will explore the policy priorities of both parties for the next parliamentary session.

"I also look forward to welcoming Mr Johnson back to Northern Ireland shortly after he becomes prime minister."

Stanley Johnson says his son Boris is up to the job of being PM because he had a "tough English education" at Eton College.

Katya Adler
Europe Editor

BBC Europe editor Katya Adler has tweeted a thread of analysis, external on continental reaction to Mr Johnson's victory.

In it, she writes: "In the often divisive Brexit world of ‘them and us’ it’s easy to forget that, beyond Brexit, EU leaders still see the UK as a close partner and ally. Today’s messages of congratulation to Boris Johnson from across Europe were a timely reminder.

"Whatever happens with Brexit, France, Germany, Poland et al still very much hope to work closely with the UK on international issues like Russia sanctions, Iran and human rights protection BUT...

"...EU leaders’ welcoming tone does not signal a willingness to accept whatever Prime Minister Johnson might demand in terms of changes to the Brexit deal. He’s right when he says a no-deal Brexit is bad for Brussels but he overestimates EU wiggle room.

"Amendments will only be forthcoming if EU leaders deem them workable, if Dublin is on board and if Brussels is convinced the new prime minister commands a majority in parliament to get the Brexit deal through once and for all. Big ifs."

She adds: "One leading EU figure describes two EU schools of thought on Boris Johnson.

"#1 That this is ´Varoufakis the sequel’: There’ll be lots of pointless meetings with PM Johnson but ultimately this will go nowhere and will result in no deal.

"#2: Because Boris Johnson was a key architect of Brexit he’s the only one that can get a compromise deal through Parliament.

"No meetings in Brussels likely over the summer, say EU diplomats. First they need to see the makeup and plan of Boris Johnson government, they say."

Image source, Conservative Party

Mark Spencer, MP for Sherwood and currently a government whip, is to be appointed as chief whip by Boris Johnson.

Leo Varadkar has tweeted to say he hopes for an "early engagement" on Brexit now that the Conservative Party has appointed a new PM.

BBC News Channel

The SNP Westminster leader Ian Blackford says "we've ministerial resignations over the last few days" and "this is unprecedented" to have resignations before a PM is even selected.

He says he is "much more confident than I've ever been" to stop a no-deal Brexit. He urges Parliamentarians "across the chamber to recognise the damage" that a no deal can do.

"We are at an impasse. Boris is not going to be able to fix this," he warns.

Image source, AFP

International reaction to this afternoon's leadership result continues, with Turkish President Recep Tayyip Erdogan the latest to issue his congratulations to Boris Johnson.

In a statement on Twitter, external, he said he wished him success in his new role.

"I believe that relations between Turkey and the UK will further improve in this new period", he added.

BBC News Channel

Liberal Democrat leader Jo Swinson says "we will see very little detail" in his speech and "frankly, Britain deserves better".

She says Mr Johnson "only cares about one thing, and that's Boris Johnson".

"This is not a man who is serious at all" in uniting the country or in the job, she says.

She says there are "millions of people" looking at Boris Johnson and Jeremy Corbyn who are "both Brexiteers" and these people "deserve something better" she adds.

"I don't think there is a majority in the country for any specific form of Brexit," she says, "three years on, the Brexiteers can't even agree" on a type of Brexit.

John Pienaar
BBC News deputy political editor

Boris Johnson will be the UK's new prime minister when he formally takes over from Theresa May tomorrow - but what exactly has the divisive MP had to do to make it this far?

Read John Pienaar's analysis here.

BBC Radio 5 Live

French President Emmanuel Macron has also congratulated Boris Johnson and promised to call him as soon as he officially becomes prime minister.

He said he was looking forward to working with him, not just on the ongoing Brexit negotiations but on international topics such as Iran.

He also paid tribute to outgoing PM Theresa May, whom he praised for never "blocking the workings of the European Union".

"She tried to best serve the interests of the British people, and in a very loyal fashion."

Environment Secretary Michael Gove - who previously had hopes of becoming PM himself - has tweeted a message of support to Mr Johnson, saying he ran a "brilliant campaign".

Mr Gove refused to say who he was backing in the final head-to-head race for leader.

The World at One
BBC Radio 4

On The World at One, Times columnist and former Conservative MP Matthew Parris says a "two to one majority" of those in the Conservative Party is not representative of those in the wider population".

"He was always going to win because he's appealing to an obsessive, ideological, extremist streak in his own national membership. He appealed to it shamelessly and it's won him the leadership, but it has not won him any sense of national consensus at all."

Reality Check

The former foreign secretary has pledged the UK will leave the EU on 31 October, "do or die", accepting that a no-deal Brexit will happen if an agreement cannot be reached by then.

He has called the withdrawal agreement "dead", but says he will "take the bits that are serviceable and get them done" - such as guaranteeing the rights of 3.2 million EU citizens in the UK.

Read more.

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