Ministers like to fulminate about the UK’s “buy now, pay later” culture. But when it comes to the sale of the state’s own assets, the government seems quite happy to take an IOU. Shareholders in British Energy, the nuclear power group 35 per cent-controlled by the government, look likely this week to be offered a share of the company’s future profits in a plan that should clear the way for it to be carved up between France’s EDF and Centrica of the UK.

As a way of breaking a stalemate over price, solutions such as these can be pragmatic. Contingency terms function like a call option, allowing the buyer to commit some money up front and then wait and see what the outcome is. They also usually create incentives for managers to stay on and work hard after the acquisition.