A giant egg from the extinct Elephant Bird which is incredibly rare is up for auction at Christie's in London.

Elephant bird eggs are the largest the world has ever seen, even larger than dinosaur eggs.

The egg, which is 30 centimetres high and 21 centimetres wide (12 inches and 8 ¾ inches), is expected to fetch up to 30,000 pounds when it is sold at the end of the month.

The egg was laid by the giant Elephant Bird in Madagascar. The species became extinct sometime between the 13th and 17th centuries. It's thought that this rare, complete sub fossilised egg would have been discovered by archaeologists in the late 19th or early 20th century.

It is so enormous it dwarfs an ordinary chicken egg and is around 120 times the size.

The Elephant Bird was the largest bird ever to have lived. Resembling a heavily-built ostrich, it would have stood up to 3.4 metres (11 feet) high. It is thought the bird was hunted to extinction.

The auction takes place in London on April 24th.

Presented by Adam Justice