Well, I think the answer is to have a deal that works for both sides. I've said that many, many times, and the Member will know my view as to what that would look like. I think it's right to say that the suggestion of any kind of apparent political border between the island of Ireland and the island of Great Britain is anathema to the unionist parties, and it's something that we've seen, of course. There are occasions, of course, where there's a great deal of cross-border co-operation. When it comes to animal health, Ireland is one phytosanitary unit; Northern Ireland is in effect not in the UK as far as that's concerned, and if you go to Northern Ireland you are asked whether you're carrying food products. That makes sense from an animal health perspective. But, no, I don't think that's workable. It would be very difficult for a UK Government to agree to that. The unionist parties would not agree to it. What is the answer, then? Well, as I've said many, many times before: stay in the customs union; the whole thing's resolved then.