Britain's Prime Minister Boris Johnson | Pool photo by Lorne Campbell via Getty Images Boris Johnson won’t start Brexit talks unless EU moves on backstop UK PM’s spokeswoman says Withdrawal Agreement ‘needs to change if there is going to be a deal.’

LONDON — Boris Johnson will not meet EU leaders until they agree to change their position on the Northern Irish backstop.

The U.K. prime minister has been clear that while he wants to meet EU leaders and negotiate a Brexit deal, he does not want "to be sat down and told that the EU cannot possibly reopen the Withdrawal Agreement and that is the message he has been giving to leaders when he has spoken to them on the telephone so far," a spokeswoman told a regular briefing of journalists in Westminster on Monday.

"The PM wants to leave with a deal, and we hope that the EU will change their position on the Withdrawal [Agreement] and the backstop," she added.

Johnson has not yet spoken to Irish Prime Minister Leo Varadkar, but Johnson's spokeswoman said he would continue to hold calls with leaders in the "coming days."

Johnson hardened his position days after the EU's chief Brexit negotiator Michel Barnier urged European leaders "to remain calm" and "stick to our principles and guidelines and show solidarity and unity" in response to Johnson's insistence that the backstop provision in the Withdrawal Agreement be axed. His comments came in a leaked letter to EU27 leaders.

But the U.K. prime minister's spokeswoman said: "The Withdrawal Agreement was rejected by parliament a number of times now and clearly it is not going to pass in its current form. It needs to change if there is going to be a deal."

Later Monday, in an interview with broadcast media, Johnson said: "I don't want the U.K. to be aloof or hanging back. I want us to engage, to hold out the hand and go the extra mile, the thousand miles. And what we wanted to do is to make it absolutely clear that the backstop is no good, it's dead it's got to go, the Withdrawal Agreement is dead, it's got to go. But there is scope to do a new deal."

He added: "I have made it very clear to our [European] friends — and we are talking to the Irish today — what the limits are, what we want to do, and we are very confident that with goodwill on both sides, two mature political entities, the U.K. and the EU can get this thing done."

Asked if he agrees with Cabinet Office Minister Michael Gove, who's now in charge of no-deal planning, that the U.K. "must operate on the assumption" of a no-deal Brexit, Johnson said: "No absolutely not. My assumption is that we can get a new deal, we are aiming for a new deal but of course Michael is absolutely right that it is responsible for any government to prepare for a no deal if we absolutely have to and that is the message I have been getting across to our European friends. And I am very confident that we will get there."

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