BRUSSELS (AP) — A daylong diplomatic ballet is playing out in the European Quarter of Brussels for another high-stakes Brexit summit.

It will culminate in a closed-door dinner where presidents and prime ministers will talk for hours and hours until no one disagrees anymore. And only then will British Prime Minister Theresa May find out when Brexit will finally happen .

But first, the Dutch prime minister is playing messenger between ally May and harder-line EU leaders. The French and German leaders are having their own huddle. A mini-club of North Sea countries is gathering elsewhere.

It is all part of the backdoor politicking that's the only way the EU can ever come to a consensus. It's baffling to outsiders — but the EU has elevated it into an art.