British celebrities Katie Price, Victoria and David Beckham, and Rupert Grint (the Ginge in those terrible Harry Potter movies) have fallen for the charms of the micro-pig, which can sell for thousands of dollars.

But the New Zealand Herald reports parents in Britain have been urged not to buy the miniature porcine pets for Christmas, with the Government set to warn this week that they risk spreading dangerous diseases.

Ministers are so nervous about the craze, which has led to several owners being mis-sold regular piglets which grow into full-size sows, that guidance is to be rushed out next week specifically targeting prospective keepers of the pocket-sized creatures.

The agency responsible for ensuring farm animals are healthy, disease-free and well looked after, will raise serious concerns about the hygiene threat posed by the animals.

It will warn: "Before buying a pig, hobby keepers and owners of pet pigs or ‘micro’ pigs must make sure they are aware of, and understand their obligations, so they can keep their animals fit, healthy and legally compliant and help them to avoid unwittingly spreading disease."

Sick pigs can pass on zoonotic diseases to humans, which can include the skin condition erysipeloid and the bacterium Streptococcus suis, which can lead to illness including meningitis and deafness in humans.

Jim Paice, the British farming minister, said: "A pig is a farm animal, not a pet for Christmas. A micro-pig may sound like a popular gift idea – but beware the pig that grows too big. This year already I’ve heard some interesting stories about micro-pigs becoming bigger and outgrowing their homes. So if you’d like to see pigs this festive season, pop along to your local petting farm."

Just not one of those E. coli petting farms.