What a relief - some sense from Labour on Brexit After a stream of utterly demoralising messaging on Brexit from Sir Keir Starmer and Rachel Reeves, it was once again left to the Mayor of London to show that some in the Labour Party see sense on this burning issue.

Sadiq Khan, speaking at the Fabian Society conference in London at the weekend, seemed more than a bit frustrated at the lack of debate within Labour about its policy on Brexit.

He criticised the “omerta” over even debating whether the UK could rejoin the European single market.

It was the departure from the single market which saw the UK lose frictionless trade with its biggest export destination, the European Economic Area. This also resulted in the loss of free movement of people between the UK and EEA, fuelling skills and labour shortages in Britain.

Labour leader Sir Keir, once a staunch opponent of Brexit who now seems to have embraced the folly wholeheartedly, and shadow chancellor Ms Reeves have continued to parrot that the UK will not be rejoining the single market or customs union.

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They do so even as polls show the UK public increasingly realises Brexit is detrimental.

From a simple economic perspective, the pair’s apparent willingness to let the damage of the Tory hard Brexit run and run for years makes absolutely no sense. Labour says it wants to boost economic growth and living standards but instead appears hell-bent on embracing the Brexit damage and ensuring it continues. This seems to be down to a fear of offending and losing the support of Brexiters.

Mr Khan, however, is not afraid. He has made plain his view that there should be consideration of whether the UK should rejoin the single market and customs union when the Brexit agreement comes up for review in 2025.

He said in January last year: “We need greater alignment with our European neighbours - a shift from this extreme, hard Brexit we have now to a workable version that serves our economy and people. That includes having a pragmatic debate about the benefits of being a part of the customs union and the single market.”

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At the weekend, Mr Khan criticised the “omerta” which he portrayed as meaning that “you can’t talk about being close to the European Union, joining the single market, joining the customs union”.

If the UK were to rejoin the single market and customs union, this would mean the Leavers still had their Brexit, but without the huge further cost of the stupidity of the Tories’ hard exit.

It might be politically easier for Mr Khan to highlight the Emperor’s New Clothes nature of the claims that Brexit can somehow be made to work than it is for Sir Keir and Ms Reeves.

After all, London, like Scotland, voted very heavily against leaving the EU in the 2016 referendum.

However, that is surely not the point.

Leaders should have the courage to tell the electorate what is what, even if this is at times not exactly what some people want to hear.

And, in any case, people are waking up to the foolishness of Brexit, even many of those who voted for it.

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Labour at times seems to have huge communication problems.

It appears to have been unable, at the time of the global financial crisis and ever since, to point out the simple truth that this economic calamity was a worldwide problem which was not its fault.

The idea that the Conservatives would have regulated the UK financial sector to a greater extent than the Labour government did at the time is ridiculous.

Yet Labour seems not to be able to get its message across.

Instead, if often seems when it comes to the economy or public finances to have decided that not being too much different from the Tories is the safe bet, even though it has been the Conservatives who have failed so dramatically on these fronts over the last 14 years.

Labour seems often to lack the courage of its convictions, and at times it appears would rather abandon these.

Even though there is a slew of numbers, a heap of evidence and a barrel-load of expert views showing how bad Brexit has been, Labour’s leadership seems unwilling to explain simply but robustly the reality of the situation or to propose meaningful action to mitigate the hit to living standards.

At times, you fear this strange stance is party-wide and then, thankfully, someone like Mr Khan pops up as a breath of fresh air, speaking simple but important truths and making entirely sensible suggestions.

Mr Khan, in an interview with The Observer published at the weekend, called for a “youth mobility” agreement with the EU.

This would certainly be a good start, given the degree to which young people in the UK have suffered by having their opportunities to work and study in the EU so terribly restricted by the Tory hard Brexit. It would also be positive for key sectors in the UK, including hospitality but also many others, which desperately need workers from EU countries to maximise their potential and help create wealth and economic prosperity.

The Observer described Mr Khan’s remarks as “one of the most pro-European interventions by a senior Labour politician since the 2016 referendum”, and this assessment of their importance seems to be bang on the money.

The newspaper reported that Sir Keir’s office had been informed of Mr Khan’s comments but did not try to block them. If that is the case, that is perhaps somewhat heartening.

Mr Khan told The Observer: “The Government’s hard Brexit has done damage right across London and it is young people who have been hardest hit in so many ways.

“Not only is it more difficult for young people to move abroad for work, but the Government’s wrong-headed decision to leave the Erasmus scheme has made it much harder for students to study abroad too.

“I’m clear that I’d be supportive of a youth mobility scheme, which would benefit us economically, culturally and socially. While the UK may no longer be part of the EU, London is, and always will be, a European city.”

The newspaper reported that Mr Khan wants “new rules to allow young people to study, travel and fill vacancies in key sectors of the economy”, applying to movement to and from the EU.

The Mayor’s focus is obviously on London.

However, implementation of such a mobility scheme for the UK as a whole would be a big step forward in restoring some common sense, giving some hope back to young people who have had so much opportunity taken from them.

That said, common sense seems to be a stranger to too many players in the Brexit pantomime, obviously among the ruling Conservatives but also more surprisingly among too many senior Labour politicians.

Mr Khan is also right about the need, before too much more time passes, for a pragmatic discussion about whether the UK should rejoin the single market. That seems like a very easy call indeed, if you are looking at it from a simple economic and societal perspective, but that is to ignore the spectacularly bizarre politics of Brexit.