Brexit might have been a mistake, says Vote Leave supremo Dominic Cummings

“No-one on Earth” knows whether Brexit was a good idea for Britain, the driving force behind the Vote Leave campaign has admitted.

Dominic Cummings, who went on to mastermind Boris Johnson’s election victory on a “get Brexit done” platform, said that he personally regards EU withdrawal as “a good thing” but admitted it could have been “a mistake”.

But, in an interview with BBC political editor Laura Kuenssberg, he said that anyone who claims to be certain whether the 2016 decision to quit the 27-nation bloc will turn out to be good for the UK would have to have “a screw loose”.

Mr Cummings also said that he and his Vote Leave colleagues had “taken over” the Conservative Party in order to “try and bend it to something that’s different”, in order not only to deliver EU withdrawal but also to “disrupt” the UK’s power structures.

And he admitted that the notorious “We send the EU £350m a week” slogan painted on the side of Mr Johnson’s Vote Leave campaign bus was deliberately chosen to “drive the Remain campaign crazy”.

Asked whether he was sure EU withdrawal was the right thing for Britain, Mr Cummings said: “I think anyone who says they’re sure about questions like that has got a screw loose, whether you’re on the Remain side or our side.

“In Vote Leave we didn’t think that we’re definitely right and Remainers are all idiots or traitors.”

Mr Cummings said he was confident on judgements of people’s ability, but added: “Questions like is Brexit a good idea? No-one on Earth knows if that’s, what the answer to that is.”

“Obviously I think Brexit was a good thing… I think that the way in which the world has worked out since 2016 vindicates the arguments that Vote Leave made in all sorts of ways. I think it’s good that, that Brexit happened.”

Mr Cummings said the £350m slogan painted on the side of Mr Johnson’s red battlebus during the referendum campaign was effective because it was based on a “true figure”, derived from the gross contribution towards EU budgets notionally required from the UK.

But it did not take into account the effect of the rebate negotiated by Margaret Thatcher or of sums returned to Britain by Brussels. The UK has in fact never sent the EU £350m a week.

As suspected by many Remain supporters, the higher figure was used intentionally in order to provoke them into discussing the UK’s payments to Brussels rather than the benefits of membership.

Asked if it was a “deliberate trap”, Cummings said: “Yeah ... the point of using that really was to try and er, to try and drive the Remain campaign and the people running it crazy.

“It helped everyone discuss what is the balance sheet?  What’s the true balance sheet?

“The reason why that figure worked and the reason why it drove everyone crazy and the reason why people are still talking about it now is that we were using true figures.”

Mr Cummings denied stirring up division in the country with “provocative” tactics to get Brexit through after Mr Johnson’s arrival in power, such as the prorogation of parliament which led to government defeat in the Supreme Court.

He said that he blamed any divisions on those who did not accept the result of the 2016 referendum, and said it would not have been possible to implement the decision to quit the EU by a inclusive “Kumbaya” approach.

“We did provoke but… the provocation was a by-product,” he said.

“The core thing was we were trying to solve the problem and show people we were trying to solve the problem.

“Was that provocative? Yes. Did we lean into that in various ways to try and disorientate the people on the other side? Yes. But, you know, that’s politics.

“There wasn’t some Kumbaya happy way, in which everyone could just sit down and go ‘Well let’s just do a friendly deal and compromise and blah blah blah’.”

• ‘Dominic Cummings: The Interview’ was being broadcast on BBC Two on 20 July at 7pm and will be available on BBC iPlayer and BBC Sounds as a podcast.