Sadiq Khan is “optimistic” about the UK remaining in the European Union (EU) and argues Brexit can be “stopped” if the Labour Party backs calls for a second referendum.

The Mayor of London also claimed Brexit had caused “hate crimes” and implied U.S. President Donald J. Trump was childish for criticizing him.

“What could trump the referendum result,” he said, “is us having a manifesto offer saying, we would not leave the EU, or we would have a second referendum.”

He told the Guardian: “For it to have credibility with the British public, there would have to be a Labour manifesto offer, because the public would say, not unreasonably, ‘Hold on a sec, we voted to leave and you’re now sticking two fingers up at us’.

“You’d have to spell out, in black and white, what we’d do if we won the general election.

“What could trump the referendum result is us having a manifesto offer saying we would not leave the EU, or we would have a second referendum.”

The London Mayor also advanced claims — questioned by police — that Brexit somehow unleashed a wave of “hate crime”, and even linked the vote to leave the EU to the Finsbury Park terror attack.

“After the Brexit vote, words that we thought had been consigned to history were being used again. Somehow, people thought they now had permission to be abusive and racist”, he alleged.

“In 2017, in the most progressive city in the world, if you happen to go to a place of worship that is a synagogue or a Jewish faith school, you need protection.

“Speak to the management team at Finsbury Park mosque and they have seen a big increase in Islamophobic attacks. We can’t be complacent.”

At least 7 dead and 48 wounded in terror attack and Mayor of London says there is "no reason to be alarmed!" — Donald J. Trump (@realDonaldTrump) June 4, 2017

After the attacks on Borough Market and London Bridge, the US president tweeted: “At least 7 dead and 48 wounded in terror attack and Mayor of London says there is ‘no reason to be alarmed’!”

Responding to Mr Trump’s criticism, Mr Khan claimed he was a “reluctant participant” in his “dialogue” with the President.

“We’re not schoolchildren … I’m unclear what his beef is with me,” he said.

Khan has campaigned to block a state visit by President Trump to the United Kingdom, and has reportedly said he would refuse to shake his hand.