Labour leadership challenger Owen Smith used a visit to Hammersmith to announce plans for the UK to remain in the European Union if he is Prime Minister.
The Welsh MP, who is challenging Jeremy Corbyn for leadership of the party, pledged that as Labour leader the party would block any attempt to invoke Article 50 until the public were promised a say on any final Brexit deal .
Speaking speech at the Studio Theatre in Lyric Theatre, which was followed by a Q&A, Mr Smith said: “The British people were lied to by the Leave campaign - they deserve to have a say on whatever exit deal the Tories strike with the EU.
“Under my leadership, Labour wouldn’t give the Tories a blank cheque.
“We wouldn’t stand idly by if Brexit meant trashing workers’ rights and environmental protections, opening our NHS up to foreign competition, making it harder for us to trade with our neighbours and damaging our economy.
“Hammersmith overwhelmingly backed the Remain campaign and 70% of the borough voted to stay in the EU.
“I’m a passionate pro-European, and I will fight tooth and nail to keep us in the EU.”
Article 50 gives UK and the EU two years to negotiate the terms of the split, with any extension having to be agreed by all 28 EU members.
Mr Corbyn’s leadership is under challenge after a string of shadow bench MPs resigned following the EU referendum. Among those to step down was Hammersmith MP Andy Slaughter , who chaired the Q&A with Mr Smith.
Mr Slaughter said: “Owen spoke powerfully of his vision for a Labour Government that will tackle the issues that matter to Londoners, like affordable homes and a properly-funded NHS.
“It’s clearly a message that appeals to Labour members in Hammersmith where he is polling 60% to Jeremy Corbyn’s 25% and 15% undecided.
“He won over a lot of those undecided voters last night because he gave them confidence that he can be not only an effective opposition leader but can win a General Election and put those plans into action.”