Johnson's full-blooded pro-Brexit rhetoric has wide support among Conservative Party members, though the speech was light on detail about his proposed alternative.
She said: "I think the reason why so many people are turned off by Brexit is because they are being fed a diet of negativity - whether it's infighting, Brussels, being disrespected by people over there".
She warned critics who want a harder break with the bloc that "if we all go off in different directions in pursuit of our own visions of the flawless Brexit, we risk ending up with no Brexit at all".
Mrs May went on: "When we've secured a good Brexit deal for Britain, at the Spending Review next year we will set out our approach for the future".
Writing talk Mrs May puts the finishing touches to her keynote speech
The move is the latest setback for Mrs May in a week which has seen 1,500 activists at the party conference in Birmingham give a standing ovation to Boris Johnson after he declared her Brexit plans a "constitutional outrage". Northern Ireland has had no functioning government for almost two years, preventing the Assembly from sitting.
Mrs May acknowledged, however, that a no-deal Brexit would be a "bad outcome for the United Kingdom and the EU".
Just six months before Britain leaves on March 29, negotiations with the European Union have ground to a halt and May is caught between Brexiteers like Johnson and those who want to keep close economic ties with the bloc, Britain's biggest trading partner.
"Whoever leads the Conservative Party we will work with as it's in the national interest", she said.
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Barcelona came into the contest winless in three straight games in their domestic league, this after losing just once in La Liga last season.
She announced a fresh drive to improve early diagnosis of cancer, plans to boost the supply of council housing and the ninth successive annual freeze in fuel duty.
She said: "Our mission as Conservatives must be to show them we can build an economy that does".
Theresa May waves after giving her keynote address on the fourth and final day of the Conservative Party Conference 2018 at the International Convention Centre in Birmingham, U.K., on October 3, 2018. Many delegates lamented the fact that Brexit has drowned out the party's message on housing, taxation, health care and other big issues.
■ On Labour's party conference: 'I listened carefully to Corbyn last week, and it was astonishing that he had absolutely nothing to say about the wealth creating sector of the economy... the grafters and the grifters'. "Her strategy is to make pleasing noises yet say very little of substance, keeping the country in a holding position until her final betrayal is unveiled at the eleventh hour".
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The nomination has become a politically explosive issue ahead of November 6 elections, when control of Congress is at stake. Senate Majority Leader Mitch McConnell , R-Ky., has vowed that the Senate will vote on Kavanaugh this week.
"Because the plan the European Union has put forward is one that effectively keeps Northern Ireland in the customs union and ensures that effectively there is a customs border down the Irish sea".
Mr Raab replied saying he didn't accept such statement and was "mindful" of the concerns of the communities of Northern Ireland.
The EU and Union flags.
May and her team face weeks of hard conversations with Brussels to win a deal, but she also faces challenges from inside her own party and from her partners in parliament, Northern Ireland's Democratic Unionist Party. "It's not taking back control".
Jose Mourinho fires warning at Manchester United squad ahead of Valencia clash
Matic said supporters at Old Trafford would see against Valencia which players were leaders and which were not. "If you talk in the dressing room, that doesn't mean anything".