Mr Van Rompuy has said that there was no impending need for treaty change between the UK and EU, but denied suggestions by Lord Mandelson that that meant he had "shot Mr Cameron's fox".
How do you convince a room full of people, when you keep your hand on the door handle? How to encourage a friend to change, if your eyes are searching for your coat?
Addressing the Policy Network EU conference in London Mr Van Rompuy continued: "Leaving the (EU) club altogether is legally possible" but it would be "a most complicated and impractical affair.
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