Right now the European Union is united on one thing above all: to get Britain to pay as big a divorce bill as possible when it exits the EU. But while money will unite leaders at this week’s European summit, it will divide them after Brexit.

The British government once hoped that the Oct. 19-20 meeting would be the moment when the Brexit negotiations could move on to discuss trade. That aspiration now seems hopeless. European leaders look set to insist on further delay until there is more progress in the first stage of talks, above all in reaching agreement on how much Britain will have to pay to settle its obligations when it leaves.

Political discord at the heart of the British government and the weakness of Theresa May following the loss of the Conservative majority in the general election have undoubtedly been hampering negotiations. Not unreasonably, European leaders worry about striking a deal with someone who might not be prime minister when Britain leaves the EU in 17 months’ time.

The EU holds the strongest cards because what matters most for Britain is its future trading arrangements with the huge market on its doorstep. The deadline under the Article 50 withdrawal procedure increases the EU’s leverage since Britain must leave with or without a deal in March 2019 (unless the 27 European states agree unanimously on an extension.) Despite hyped-up talk in London about preparing for no deal at all, Britain will do its utmost to avoid what would be a ruinous outcome, grounding flights to Europe and causing long hold-ups at border crossings, such as Dover on the south coast of England.