Before the General Election, I was one of 16 London Labour MPs who supported a Vote Leave Watch pamphlet setting out why membership of the European Single Market was vital for London's economy, and why therefore we should stay in it after we leave the European Union. Today, it's brilliant to see the Mayor of London, Sadiq Khan, backing that call.
In a statement today, Sadiq said that in the aftermath of the General Election, "the Government must now listen to the will of the people by putting aside ideology, and negotiating a sensible Brexit that ensures continued membership of the Single Market."
He's absolutely right. Working people have benefited from Britain's place in the Single Market - and the Customs Union - and it is they who would suffer the most from a hard, destructive Brexit that wrenches our country out of its biggest market.
The crucial thing about the Single Market is not just that it provides tariff-free trade in goods. What it does, which is not matched by any other trade agreement on Earth, is provide a framework of rules which simultaneously frees trade while also protecting working people, consumers, and our natural environment from rapacious global capitalism.
From the Working Time Directive, which prevents people from working dangerously long hours, to the Habitats Directive, which protects animal life, to judgements of the European Court of Justice preserving workers' holiday pay, the Single Market has benefited working people. That's why people from across the Labour Movement, like TUC General Secretary Frances O'Grady, back continued British membership.
On the other side of the argument, you have the Tory hard Brexiteers like Boris Johnson, Michael Gove, David Davis and Priti Patel. These are people who want to use our exit from the European Union to take a big pair of scissors to so-called "red tape" - that is, the laws and regulations that protect ordinary people from the worst excesses of the free market. I am glad that Sadiq has taken up the cudgels against a Tory hard Brexit, in addition to the 50 Labour politicians, including me, who wrote a statement to the Guardian making the same point earlier this week. Our party should be united in rejecting the Tory approach; a strong opposition must mean that we never give them political cover to carry out damaging policies like leaving the Single Market.
The Single Market and the Customs Union create jobs for working people in Britain, by breaking down barriers to trade. Any resurrecting of these barriers will put jobs at risk, which is why I and 30 other Labour MPs have put down an Early Day Motion in Parliament supporting our continued membership of the Customs Union.
To take power at the next General Election, Labour must continue to appeal to the millions of younger people who flocked to our banner on June 8th. They are overwhelmingly pro-Remain, and they know that their interests and our country's future are best served by a close relationship between the UK and Europe. That must mean continued membership of the Single Market.