THE best kept secret in the canine world is finally out as the Duchess of Cambridge has revealed that Lupo is the name of the cocker spaniel she shares with her husband, the Duke of Cambridge.

Royal insiders have been tight-lipped about the name of the black puppy since the Duke and Duchess introduced him into their home at Anglesey, North Wales, last year.

But the temptation to share the name with the public has prove too big for the Duchess to contain. She let it slip during a visit to one of her charities in Liverpool recently and finally spilled the beans in a public way during a visit to another of her charities in Oxford this week.