The Brexit ‘divorce bill’ is supposed to settle existing obligations, rather than cover the cost of any future agreements. Some therefore argue that it is simply a matter of honouring past debts and the UK should just pay up. The problem with this approach is that there is no legal certainty...

The UK is leaving the EU and needs to close its accounts. In a divorce, the two sides divide up the assets and liabilities. But the situation here is more like leaving a club, so the question is when the obligation to pay membership fees should end. One option would be simply be for the UK to...