Theresa May reveals irritation at Boris Johnson, accusing him of 'tearing up our guarantee to Northern Ireland'

Theresa May has revealed her irritation at Boris Johnson stealing the limelight at the Tory conference, accusing him of trying to “tear up our guarantee to the people of Northern Ireland”.

The prime minister said the rousing call by the Tory faithful’s favourite for her to “chuck Chequers” – made to a packed-out hall of supporters – had made her “cross”.

She also refused to discuss his future leadership prospects, insisting she was more interested in “the jobs of people out there in our country”.

The interview followed Mr Johnson’s hotly-anticipated appearance at a fringe meeting which drew huge queues hours before it started – in stark contrast to a main hall half-empty even for cabinet ministers’ speeches.

The former foreign secretary, who resigned over the Chequers plan, accused the prime minister of trying to “cheat” Brexit supporters with proposals that would leave the UK in “manacles”.

He also launched a broader attack on her crime and taxation policies, in what was widely seen as an appeal to Tory members ahead of an expected leadership bid in the near future.

Asked about the event, Ms May said she had not watched it, because she had been “meeting activists” and “seeing a party that's in really good heart”.

But she told the BBC: “There are one of two things that Boris said that I'm cross about. He wants to tear up our guarantee to the people of Northern Ireland.

“Northern Ireland is part of the United Kingdom. We are all - he and I and all members here - are members of the Conservative and Unionist Party.

“That's because we believe in the union of the United Kingdom. Northern Ireland is part of that union.

“We have a guarantee for the people of Northern Ireland and we are upholding that. Our Chequers plan does that. It is the only plan on the table at the moment that does.”

In his speech, Mr Johnson called on her to abandon attempts to reach agreement on the so-called “backstop” to prevent a hard Irish border, in the absence of other solutions.

He is urging a looser ‘Canada-style’ trade deal instead, but Brussels has insisted that must mean Northern Ireland remaining aligned with the EU on customs and regulations – to prevent border checks.

Asked if Mr Johnson was a future prime minister, Ms May replied: “I'm not speculating about or commenting about jobs for individual members of parliament.

“This is not about the jobs of politicians, this is about the jobs of people out there in our country, it is about protecting those jobs for the future."

The prime minister also told Sky News: “Boris always puts on a good show but what matters to people is what we are delivering for them on the things that affect their day to day lives.”

The prime minister’s traditional round of interviews, ahead of her close-of-conference speech on Wednesday, provoked an unprecedented protest from broadcasters.

They were angry at No 10 limiting her appearances, which meant Channel 4 and Channel 5 missed out – even comparing the decision to Donald Trump’s treatment of the media.

“For a functioning democracy, it is vital that in turn the politicians, and in particular the leaders and even prime ministers, are also questioned and held to account in one-to-one interviews,” a joint protest letter said.