David Miliband speaks onstage during the 2018 Concordia Annual Summit | Riccardo Savi/Getty Images Labour must become ‘unequivocal’ party of Remain, says David Miliband Former foreign secretary says it is clear the opposition party’s Brexit strategy is not working.

The U.K. Labour Party must change course to become the “unequivocal party of a people’s vote” and advocate for remaining in the EU, said former Foreign Secretary David Miliband.

Speaking to POLITICO, Miliband said the party’s current strategy on Brexit is failing badly — it achieved just 14 percent of the vote in the European Parliament election last month.

Miliband, who is from the moderate wing of the party and has been a critic of current leader Jeremy Corbyn, said Theresa May’s Tory government is “dysfunctional and useless” and so Labour’s failure was all the more stark.

“Clearly this isn’t a matter of whether or not you believe that Labour should appeal to Leavers and Remainers. Of course it should,” said Miliband. “The question is how do you do so? You don’t do so by sitting on the fence. That’s evidently the case.”

The former foreign secretary, who since 2013 has been based in New York as head of the International Rescue Committee, an NGO that helps refugees and displaced people, countered the assertion from Brexiteers that a second referendum would be undemocratic.

“We don’t know which Boris Johnson is going to come to lead the country” — David Milliband

“The Brexit that people are now being offered is so different to the Brexit that was promised at the time of the referendum that it would be undemocratic not to have a confirmatory ballot,” he said.

Miliband said he understands why a group of Labour MPs defected from Labour to form Change UK. "They were obviously provoked beyond all endurance and one shouldn’t question their personal integrity ... I mean lots of people are having their party loyalties tested to the limit,” he said.

He said he had been in touch with the group of MPs before they broke away from Labour. “Yes of course I talked to them. I didn’t talk about their party plans,” he said, “There are lots of people who are deeply concerned about, not just the political strategy of the Labour Party but where it is being taken.”

Asked if former Labour spin doctor Alastair Campbell should have been expelled from the party for saying publicly that he had backed the Liberal Democrats at the European election, Miliband said: “Of course not. I mean he’s sort of Labour to his … bone marrow. So [it was] absurd to expel him … I think it’s made the leadership look utterly foolish.”

But Miliband added that he remains a party member and had voted Labour in the European election. “The truth is that the Brexit nightmare has to be worked through by the existing party system. I’ve always felt that,” he said.

On the Tory leadership contest, he said it is “extraordinary” that Boris Johnson is leading the race to be prime minister given his record as foreign secretary.

“The truth is we don’t know which Boris Johnson is going to come to lead the country,” said Miliband, “And that’s a problem because someone who has taken so many different positions and so many different personas obviously engenders a high degree of mistrust.”

Miliband was in Brussels to speak at the European Development Days conference on Tuesday. He argued that with the U.S. stepping back from international affairs, only the EU has the power to keep the Sustainable Development Goals, which were agreed by the U.N. five years ago, on track.

“They are off track in fragile and conflict states. Those are places where more people are living in extreme poverty so I think that it is really important to have focus and to have clarity … the EU is the body that has the greatest opportunity to do this,” he said.

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