Former Tory Chancellor George Osborne has said “mistakes” led to the Brexit vote and that people should not have been given a say on the European Union (EU) as it “opened up the door” to the Leave vote.

David Cameron’s former right-hand man said their government had been too slow to address concerns about mass immigration and make people appreciate being ruled from Brussels in an interview Tuesday night.

He also said the Tories, with Theresa May as Home Secretary, should not have promised to slash immigration when they did not have the power to control borders and claimed that giving away sovereignty to organisations like the EU was an inevitability in the modern world.

Speaking on BBC’s Newsnight, he said: “I think we were wrong to play into the debate that everything that Brussels did was a challenge and a battle and was wrong.

“On immigration, we were promising targets that we couldn’t deliver and that then led to a debate about how you might deliver those targets – not that I see any evidence that they’re going to be delivered in the future – but, you know, we definitely contributed to that argument, didn’t make enough of the value of immigration.”

George Osborne on the things “we got wrong”… “We didn’t spot the shift in politics .. on immigration we were promising targets that we couldn’t deliver"#newsnight | @EvanHD | @George_Osborne pic.twitter.com/qfkZnhWARj — BBC Newsnight (@BBCNewsnight) October 30, 2018

Mr Osborne, who now edits the Evening Standard, also claimed that constitutional sovereignty was a “minority concern” and said linking it to concerns about immigration was “pretty lethal” for the pro-EU cause.

“It opened up the door in the referendum… essentially it allowed in the referendum a minority of people who were interested in rather esoteric issues of a sort of constitutional sovereignty.”

“We were too late in the day trying to explain some of the benefits of European Union membership. So I’m happy to look at mistakes we made,” the former Chancellor added.

What George Osborne overlooks is Referendum win was more about self government and sovereignty (49% of Leavers – Ashcroft poll) than immigration (33%) – but control of borders IS about sovereignty. That was never understood or acknowledged by Remain https://t.co/f3kJNbCq6K — David C Bannerman (@DCBMEP) October 31, 2018

He also defended globalism and centrism, and claimed the Tories lost their majority in 2017 by trying to “out-UKIP UKIP” and would not win the next election “by trying to out-Corbyn Corbyn.”

“Trying to bang the nationalist drum doesn’t actually work for modern conservativism and trying to outspend our political opponents isn’t going to help the Conservatives either,” he said.

UKIP’s current leader, Gerard Batten, hit back in a statement, argued that Mr Osborne and pro-EU Tories were being dishonest and ignoring the will of the people.

He said: “Mr Osborne calls his government’s actions in office ‘mistakes’. They were not mistakes, but the willful attempt to submerge the UK into an EU superstate without regard for the concerns of the people.

“As for their immigration targets, they were never going to be met while Britain remained stuck with open borders inside the EU.

“Add to that an incompetent Home Office under Theresa May staggering from one immigration scandal to another and you end up with a net migration figure of 1.745 million people from 2010-2016 and that’s just the documented figure.

“The Tories have always built their brand on controlling immigration, yet when we look at the facts they do nothing of the sort. The only regret Mr Osborne has is giving the people a say in their future, which says a lot about his attitude towards the electorate.”