Donald Trump has congratulated Boris Johnson on his landslide victory in the Tory leadership race, saying he will make a “great” PM.
The US President tweeted his best wishes to Mr Johnson, who will take the reins from Theresa May tomorrow.
Mr Johnson won the ballot of Tory members by a landslide margin of 2-1, securing 92,153 votes.
Defeated candidate Mr Hunt congratulated Mr Johnson on a “campaign well fought”.
He tweeted: “You’ll be a great PM for our country at this critical moment. Throughout campaign you showed optimism, energy and unbounded confidence in our wonderful country and we need that.”
EU chief Brexit negotiator Michel Barnier said his team is looking forward to working with new Tory leader to “facilitate the ratification of the Withdrawal Agreement and achieve an orderly Brexit”.
Labour leader Jeremy Corbyn said that while Mr Johnson had won the Tory leadership contest, he “hasn’t won the support of the country”, adding: “The people of our country should decide who becomes the Prime Minister in a General Election.”
As expected, Mr Johnson’s appointment as leader sparked a polarised reaction among local politicians.
DUP leader Arlene Foster tweeted her congratulations to Mr Johnson, adding: “Look forward to discussing our shared objectives of strengthening the Union, delivering Brexit & restoring devolution.”
Earlier Mrs Foster tweeted a photograph of her watching the announcement live at her constituency office in Enniskillen, Co Fermanagh, describing it as a “historic day”.
Ulster Unionist Party leader Robin Swann also congratulated Mr Johnson on his imminent appointment as Prime Minister.
He added: “There is now immense expectation as to the next steps the new Prime Minister will take and one of those must be the restoration of a functioning Northern Ireland Assembly. The Ulster Unionist Party is willing and able to work with Mr Johnson to ensure this happens but if that is unattainable in the short term, then he must move to ensure further critical decisions are taken by Westminster.”
He added that the new PM must do “everything possible” to avoid a no-deal Brexit.
“I urge him not to allow nationalism in Northern Ireland or Scotland to exploit the current instability for selfish political interests,” he said.
The north Antrim MLA also paid tribute to Mrs May for her service to the United Kingdom, adding: “One thing that was never in doubt during her tenure was her belief in the Union.
Ulster Unionist Peer Lord Empey said Mr Johnson faces “many onerous tasks and huge political decisions” in the months ahead.
He added: “I strongly encourage him to continue to seek alternatives to the backstop which threatens Northern Ireland`s position within the United Kingdom. We have suggested alternatives and I hope he can take them on board as a part of a potential solution to the political bind which the EU and UK currently find themselves in.”
Alliance Party leader Naomi Long MEP said the UK needs a “statesman, not a showman”.
She continued: “At such a critical juncture, we need someone who is detail focused and sensitive to the complexity of the challenges ahead.
“Boris Johnson’s road to the Conservative Party leadership has been paved with destructive half-truths, bluster and outright lies, many of which helped precipitate the crisis from which he is now personally benefitting. With an impending no deal Brexit and the stark choices facing us, we need substantive answers from him to what are incredibly serious and complex questions.”
She also accused Mr Johnson of failing to demonstrate “any real understanding” of the needs of Northern Ireland, particularly in the context of Brexit and especially in a no deal scenario.
“The Irish border is a delicate and nuanced issue, with resonance far beyond trading arrangements and with the potential to unpick the fabric of the Good Friday Agreement if mishandled,” she said.
“It is also impacting on the ability of parties to restore the political institutions here. He now needs to demonstrate his ability to act with sensitivity and impartiality in his engagements with local parties.
“It’s time to cut the bluff, bluster and bombastic rhetoric, and start to provide the kind of reassurance business and civic society needs. Whilst I remain sceptical he will do that, I wish him well and will be more than happy to be proved wrong.”
SDLP leader Colum Eastwood described Mr Johonson’s appointment as a “worrying step toward a hard no-deal Brexit and a hard border in Ireland”.
“Johnson has coasted into Downing street on a wave of Brexit bluff and bluster,” Mr Eastwood said.
“It won’t be long until he crashes into the rocky reality that the European Union will not sacrifice the interests of Ireland to appease a man who has lied and slandered its institutions in an effort to secure power.
“All parties in the North must now set our combined efforts to resisting the impulse of this administration to drive off the Brexit cliff edge.”
On behalf of the Presbyterian Church in Ireland, the Moderator, Right Reverend Dr William Henry, offered his congratulations to Mr Johnson.
In a letter to the next PM, Dr Henry will urge him to take “a keen and personal interest” in the inter-party talks to restore devolution and to “actively encourage those involved to go the extra mile”.