At paragraph 4 of their guidelines, they say that it is the UK’s positions,
“which limit the depth of such a future partnership”,
and that:
“Being outside the Customs Union and the Single Market will inevitably lead to frictions”.
But they also say at paragraph 6 of their guidelines that if the UK’s positions on the customs union and the single market,
“were to evolve, the Union will be prepared to reconsider its offer”:
in other words, to improve its offer. We do not know how far-reaching such improvements would be but, if we go on refusing to allow our negotiators to explore the idea of a customs union, we will never find out, and that in my view will be irresponsible—hence the wording of the amendment. I do not recall at the time of the referendum any debate about a customs union.