If an EFTA-style arrangement —of course, a country cannot belong to EFTA if it is a member of a customs union—with a customs union were introduced, I see no reason why it would not satisfy the stated objectives of the backstop in protecting the hard border and north-south co-operation. The hon. Gentleman asked whether the arrangement is terminable. I think it is terminable on 12 months’ notice, but I may be wrong. However, a customs union would fall to be negotiated specifically with the European Union, and one would have to insist upon such a termination clause in that union. That would be a question of agreeing it with the Union.