Plans to keep Britain in the customs union after Brexit could win the backing of a majority of MPs today after a senior member of the shadow cabinet warned that Labour was only likely to support a Brexit plan that allowed immigration reform.

Emily Thornberry, the shadow foreign secretary, hinted that Labour would again be unable to back the Common Market 2.0 plan, under which Britain would stay in the customs union and the single market, because it meant maintaining freedom of movement.

Tonight MPs will consider nine alternatives to Theresa May’s Brexit plan in a second round of indicative votes. They range from a second referendum or a no-deal exit at the end of next week to letting parliament revoke Article 50, postponing