Senior Labour MPs have said for the first time since cross-party talks began that Mrs May’s ‘red lines’ may have started to shift.
These entrenched positions surround a closer customs union with the EU after Brexit.
It was feared the negotiations would finish without and breakthrough next week after local elections on Thursday, but it is now thought the discussions will continue, according to the Times.
Theresa May and husband Philip May arrive at the Midland Hotel, greeted by Andrew Sharpe, president of the National Conservative Convention
A Labour source told the newspaper: ‘There wasn’t complete movement but there was movement.’
The talks are expected to run into next week after several hours of discussions led by Mrs May’s deputy, David Lidington, and John McDonnell, Labour’s shadow chancellor.
As Labour and the Tories start a fifth week of Brexit talks, Jeremy Corbyn’s MPs are due to meet to heap more pressure on him to back a second referendum.
The Parliamentary Labour Party of its 229 MPs will meet in Westminster to discuss the issue.
Despite a letter signed by 115 Labour MPs and MEPs for the party to campaign for second referendum, the NEC is not expected to shift party policy.
Theresa May arriving by the back door of No 10 this morning as Brexit talks continued
Chancellor Philip Hammond has been at the Whitehall Brexit talks with his counterpart John McDonnell today.
Mrs May was also warned she will face an unprecedented confidence vote from Tory activists unless she agrees to step down within weeks.
Andrew Sharpe, head of the party’s voluntary wing, is understood to have delivered the ultimatum during talks with Mrs May in No 10.
Under party rules, such a meeting must be convened if the chairmen of more than 65 Tory associations demand one.
Mr Sharpe told Mrs May more than 70 chairmen had now written voicing no confidence in her following her failure to take Britain out of the EU on time.