LONDON —  A growing majority of British people now want Theresa May to call a second Brexit referendum if she fails to secure a deal on Britain’s exit from the EU.

57% of voters who stated a preference, said they would want another vote under those circumstances, according to a new BMG poll.

Among younger voters, the majority is even larger, with 73% of 18-34-year-olds now backing a second vote.

The poll also found overwhelming support for the second referendum among Labour voters, with 74% calling for a new vote if May fails to win a deal. A separate poll conducted by Comres last week found that voters would now back Remain if Britain went back to the polls. It found 55% would now support Remain, with 45% backing Leave, according to the poll for the Daily Mirror.

The findings will put pressure on May to rule out leaving the EU without a deal. The prime minister has previously repeatedly insisted that:

“No Deal is better than a Bad Deal.”

Labour has also so far refused to back calls for a second referendum, despite support among Labour voters and members. “We are not supporting or calling for a second referendum,” Labour leader Jeremy Corbyn told ITV on Sunday.

Shadow Brexit secretary Keir Starmer told Labour MPs on Monday night that the party should not “look back in grief” at the result of the referendum. “It is a really important distinction: Are we looking back in grief or looking forward to the challenge of the future,” he said.

Josiah Mortimer, the editor of the Left Foot Forward website, which commissioned the poll, said it would make “uncomfortable reading” for both May and Corbyn.

“If the PM fails to secure a proper deal with the EU, most voters with a view want a fresh in/out referendum on our membership.” He added: “Jeremy Corbyn is at odds with most Labour supporters on the issue as he tries to juggle competing demands. More and more of his own backers are coming out in support of stopping Brexit altogether.”