He's still cuter than your average bear but he's no longer a baby, and those teeth are getting sharp.

Berlin zoo announced today that its fast-growing polar bear cub, Knut, will no longer be making his public appearances with Thomas Doerflein and Ronnie Henkel, the keepers who have raised him.

The twice-daily shows have been the zoo's biggest draw since Knut - then weighing just 9kg (20lb) - made his first public appearance in late March.

Now, at the age of seven months and weighing nearly 50kg (110lb), the bear is too big for the shows to continue safely. He will remain on public view but will have his enclosure all to himself.

A zoo spokeswoman said that the move would also help prepare Knut to “associate with other bears and not with other people”.

Born on December 5, Knut has been raised by Mr Doerflein and other zoo staff after his mother rejected him and another cub that died. He went on public show on March 23 after the zoo rejected calls from environmentalists that he should be put down because it would be unnatural for him to be raised by humans.

Mr Doerflein will remain on hand for Knut even if their play sessions have been called off.

“This doesn’t mean that I will never play with Knut again - it just means there are no fixed times anymore,” he said. “I am always there for him. Knut is still a child. He needs me.”

Mr Doerflein added that he feels "burnt out" after months of frolicking with Knut and has not always enjoyed being a celebrity in his own right.

"That is the worst thing. People want autographs, to touch me," he said. "When I am with my girlfriend, they want to buy me a drink. When I say ’no,’ they get aggressive."

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