TWO of Labour’s most senior politicians publicly clashed over the possibility of a second referendum on Brexit yesterday after mayor of London Sadiq Khan came out in favour of a “people’s vote” on any final deal secured by the government.

The party’s shadow international trade secretary Barry Gardiner said a fresh referendum would be a boost for the Tories.

Meanwhile, the Scottish LibDems claimed Khan’s comments put pressure on Richard Leonard who has so far remained quiet on the issue.

The row came as a new poll suggested half the public believe Brexit will have a negative impact on the country, and just 41% believe it will be positive.

The ComRes survey for the BBC found that a majority of voters – 79% – is critical of the government’s handling of the exit talks, and just one-third think they will be better off in five years as a result of Britain quitting the European Union.

Writing in The Observer, Khan said he didn’t believe May had “the mandate to gamble so flagrantly with the British economy and people’s livelihoods”.

Khan, who after the first referendum dismissed calls for a second saying it would lead to “even more cynicism”, says he has changed his mind because of the “abject” performance of the government. “This means a public vote on any Brexit deal obtained by the government, or a vote on a ‘no-deal’ Brexit if one is not secured, alongside the option of staying in the EU,” he wrote.

“People didn’t vote to leave the EU to make themselves poorer, to watch their businesses suffer, to have NHS wards understaffed, to see the police preparing for civil unrest or for our national security to be put at risk if our co-operation with the EU in the fight against terrorism is weakened.”

Gardiner told Sky News’s Sophy Ridge On Sunday: “Calling for a second referendum is really giving her a lifeline because then she can say ‘Oh, if I can’t get it through parliament I’ll go back to the people’.”

He said that the first referendum had caused “real divisions” in the country.

“I think the challenge now is to try to heal society,” he said.

Meanwhile, Scots Tory leader Ruth Davidson was asked about May’s Brexit plan during an interview with The Sunday Times, and hinted she thought there could be agreement between MPs, and negotiating teams in London and Brussels, if it was a “Chequers-based deal”.

When asked for a solution to the Northern Ireland border, the MSP said: “I think there is a realisation that because no-one has ever left the EU before, a lot of this is new and different.”

When pushed again for her solution, she replied: “For me, I think there is a deal to be done that allows, over time, for regulatory alignment.”

Any form of regulatory alignment would be unacceptable to Northern Ireland’s DUP.