Pressure increases on Jeremy Corbyn as Sadiq Khan urges Labour MPs to be brave on Brexit

Mr Khan – Labour’s most senior elected politician – said the series of votes expected later this month would “define” today’s generation of Labour MPs.

Although Labour’s leadership supports 14 of the 15 amendments. lifelong Eurosceptic Mr Corbyn is widely expected to order his MPs to vote against peers’ plans to keep Britain inside the European Economic Area (EEA), which is seen by Brexiteers as the same of staying in the EU single market.

Mr Khan told the Guardian it was ‘extremely rare that parliament faces a vote that is more important than party politics, more important than MPs’ ministerial careers and which will define that generation of parliamentarians in the history books’.

Invoking the memory of Labour MPs who voted against the 2003 Iraq War, Mr Khan said: ‘The last vote of this significance was the vote on the Iraq war – when there were brave MPs from all parties who did the right thing and voted against the war regardless of the consequences.’

Mr Khan himself was not in the Commons at the time, having only become an MP in 2005.

‘Parliament has the opportunity to reject the Tories’ shambolic and reckless handling of Brexit and preserve our prosperity for the next generation – if MPs are brave,’ the Mayor said.

The 15 amendments passed by peers include an effort to keep the UK in the EU single market and a custom union after Brexit – both of which have been ruled out by prime minister Theresa May.

Others would gives Parliament a meaningful vote at the end of talks and a veto on the government’s negotiating position, while another would ensure the EU’s environmental principles were enshrined in UK law.

The government is most likely to face defeat over the issue of remaining in “a”, if not “the”, customs union.

Mr Khan has previously argued that the UK should remain in both the customs union and the single market, as he attempts to reflect the views of a city where 59.9% of people voted Remain.

Eloise Todd, CEO of the anti-Brexit campaign group Best for Britain, said: “Labour has a unique chance to change the dynamic but they must move their position on Brexit. This car crash of a government is offering Labour a chance to win. Sadiq has asked MPs to be brave. “Best for Britain research is showing that seats, especially in the south, are there for the taking if Labour harden their position against Brexit, and research also shows that around half of Labour leave voters support a People’s Vote already and one in seven Labour supporters that voted leave have switched to wanting to stay in.

“Labour must stand up against this divisive Tory Brexit and this is the potential, a once in a generation chance to shake up the electoral map and lock in a Labour majority for the next election. “This is their chance, they should grasp it.”