Labour leader Jeremy Corbyn has stopped short of ruling out a second EU referendum when the Brexit terms are known.
Mr Corbyn insisted he was not calling for a new national poll on withdrawal, but sidestepped questions on whether he could change his stance in the future.
The Labour leader told ITV’s Peston On Sunday: “We are not supporting or calling for a second referendum. What we have called for is a meaningful vote in Parliament.”
When it was put to Mr Corbyn that he was not saying he would never support another referendum, the Labour leader said: “We are not calling for one either”.
Asked about a second referendum on any Brexit deal, shadow foreign secretary Emily Thornberry told BBC1’s Andrew Marr Show: “If 90% of the population was now saying we must stay in the European Union and we must not leave then that would be a challenge that would be there for all of us who are democrats.
“But, at the moment, and as things currently stand, we proceed in good faith, we do as we are instructed and we are leaving the European Union.
“We have said that we must respect the result of the referendum which means that we have to leave, but we have to look after the economy which, in my view, means that we don’t go very far.”
Deputy Tory party chairman James Cleverly said the comments showed that Labour was trying to frustrate Brexit.
He said: “Once again the very top of Labour, this time Jeremy Corbyn and Emily Thornberry, have failed to rule out a second referendum.
“Every step of the way Labour are trying to frustrate the Brexit process rather than make a success of it.
“Labour just can’t be trusted to deliver on leaving the European Union.”
Mr Corbyn also has hit back at Labour critics calling for the UK to stay in the single market after Brexit.
The Labour leader said: “The single market is dependent on membership of the European Union.”
The comments came after some Labour figures called for the party to change tack and campaign to remain in the single market and customs union after withdrawal.
Mr Corbyn expressed concern about some parts of the single market set-up.
“There are also aspects of the single market one wants to think about such as the restrictions on state aid to industry, which is something that I would wish to challenge.”
Mr Corbyn said Labour would vote against landmark Brexit legislation which returns to the Commons in the next few days unless its demands were met in areas such as workers rights.
“If our tests are not met by the Government then we will vote against the Bill.”