Rachel Reeves risks a Brussels shake-down

While deals on plant and animal health, and on electricity trading, bring obvious benefits to EU farmers selling food to Britain and to northern European customers buying British energy, Charles Grant, at the Centre for European Reform, says even in these limited areas it is hard to strike a deal.

Even with those benefits “there is not a lot of enthusiasm” in Paris, Berlin and Brussels for closer ties.

And it comes with costs for the UK.

“The British have to, in return, agree to accept dynamic alignment with EU rules, accept a role for the Court of Justice, and have to pay some money into the EU’s cohesion funds – how much, people do not really know,” he says.

“If the British ask for more areas, for example chemicals, pharmaceuticals, medical equipment or even automobiles, how will the EU react? There is not yet an answer to that question. The EU does not see a very clear interest in other areas yet.”

He suspects that over time, and with greater political distance between the EU and the US, the need for British military resources will encourage Europe’s politicians to offer more access to markets too.

For now, the far the main dividing line is between the Baltics and Nordics nations – which, given the threat of Russia on their doorstep, are keen for more British involvement – and the French who “take a very hard line in the opposite direction”, says Grant.

“As time goes on, and the more European security is a worry, because of Trump’s behaviour and Russia’s behaviour, there may come a time that the need to involve Britain in European security makes the EU a bit more flexible on the single market - especially if Britain is prepared to pay more money,” says Grant.