JEREMY CORBYN wants a Brexit that would produce a similar trading relationship between Britain and the EU to what exists today.

In theory it sounds like a sensible way forward. Mr Corbyn’s stance was widely welcomed by Britain’s business leaders, and even the most ardent Brexiteer must have heard some merit in Monday’s speech.

If the plan helps avoid the need for a hard border in Northern Ireland, for example, then any sensible person would surely back it. But is a customs union with the EU after Brexit a realistic objective? It would effectively mean Britain had the right to veto new trade deals in the same way as a full EU member. You cannot imagine Brussels would agree to such an arrangement.

Remainers will be dismayed that Mr Corbyn resisted calls for the party to become a rallying point for those determined to stay in the single market and press for a second referendum. But Labour’s policy shift undoubtedly heaps pressure on Theresa May as she faces a potential rebellion from members of her own party who oppose her commitment to leaving the union.

It opens the door for rebels such as Anna Soubry to join a soft Brexit alliance, and increases the likelihood of Mrs May losing the Brexit bill showdown, being ousted from office, thus forcing a General Election.

When push comes to shove it is unlikely that Tory rebels would go so far as to help bring down their own government but Mrs May now has her work cut out to bring the warring factions of her party together or see one side drift ever closer to Labour.