Britain’s opposition Labour Party will seek to prevent Prime Minister Theresa May’s successor taking the country out of the European Union without a deal, its finance spokesman John McDonnell said on Sunday.


May said on Friday she would step down next month, and several of those vying to replace her have said Britain must leave the EU on its Oct. 31 deadline even if that means quitting without a deal.


“There is real threat now of an extremist Brexiteer becoming the leader of the Conservative Party and taking us over the cliff edge of a no deal,” McDonnell told Sky News, saying Labour was seeking to work with other opposition parties.


“We have got to move forward now, bring people together and block a no deal and if that means going back to the people (for a second referendum), so be it.”