What is Johnson’s real red line in EU trade negotiations?

Is the prime minister truly bluffing when he says he is prepared to walk away if he doesn’t get what he wants, asks John Rentoul

By June, the government will have decided whether they are going to continue negotiations (EPA)

There is a lot of bravado, posturing and spin in Boris Johnson’s opening gambit for the trade negotiations with the EU. Ten days ago, David Frost, the prime minister’s negotiator, gave a punchy lecture in Brussels in which he accused the continentals of dismissing Britain’s legitimate desire for independence as “irrational false consciousness”.

Yesterday, the government published its negotiating mandate, a 36-page document setting out what it wants from a deal. The document suggests that the negotiators will walk away if the “broad outline” of a deal has not been agreed by June. That is the deadline for the UK government to ask for an extension to the transition period beyond December, but Johnson has said he will not do so.