Charles had to make his own calculation. If he told them about Gareth’s disappearance the submission would have to be redrafted and resubmitted with a strengthened risk assessment, which would mean it was less likely to obtain the prime minister’s agreement. At the same time, all concerned – prime minister included – wanted the operation to go ahead. If it contributed even in a small way to a reasonable settlement, it was in the national interest that it should do so. If, meanwhile, Gareth intended to expose all in the press or on the web then the damage would be done whether or not Charles’s lunch with Timber Wolf happened. But Charles felt Gareth would not blow everything, or not yet. Whatever hidden bitterness he might feel towards the Office or Charles personally, he would surely be reluctant to expose his old friend Timber Wolf. So Charles hoped.

‘We’ve no evidence so far that he’s in that frame of mind,’ he said.

The Brexit secretary’s gaze continued. ‘You’re keeping an eye on him?’

‘We’re involving MI5.’

‘Now the message, the message you’ve got to get over,’ said the foreign secretary, ‘is essentially this: that the absolute max we’ll pay for the so-called divorce settlement is twenty per cent above the figure that’s in the public domain as our max. That’s a significant concession, large enough to create political difficulties here but manageable. Not a penny more. That would be politically and publicly unacceptable. Second thing you’ve got to get over is that if the trade negotiations don’t yield a deal that’s reasonable for both sides, then we’ll walk away, taking our divorce payment with us. You may not hear the prime minister repeat in public that no deal is better than a bad deal but that’s still our position. Nothing is agreed until everything is agreed, remember. We really will walk away and they’ve got to be made to believe it, which they don’t yet. Preparations for no deal are in progress. Simon here has a note of the precise form of words the prime minister wants put over.’

The private secretary read aloud a few sentences from his notebook. It sounded like a list of abbreviated bullet points. Listening and at the same time considering how to put it over reminded Charles of his recent telephone conversation with Timber Wolf, setting up the Monday lunch. He had rung him in his office, something he would never normally do with an agent, but it was in keeping with the fiction that neither had anything to hide.