Britain's Prince Charles wants grey squirrels exterminated.

The future king - a keen environmentalist - has claimed it is essential to eliminate the animal, introduced from North America in the 19th century, because of the threat they pose to native red squirrels.

In a letter to the Country Land and Business Association, Charles - patron of the Red Squirrel Survival Trust said: "In order to be able to save the red squirrels and ensure their future in this country, it is absolutely crucial to eliminate the greys which, as you know, are an alien species to the UK and threaten the very existence of the reds.

"As you are also no doubt aware, the greys are doing immense and increasing damage to hardwoods all over the country and threaten to compromise all our efforts to restore native woodlands, let alone to create community forests."

His comments have been supported by many conservationists, who blame the greys for spreading disease, destroying trees, wrecking homes and gardens and killing birds.

However, the RSPCA said a cull would be cruel, with a spokesman saying: "We are concerned about the welfare of both red and grey squirrels, and believe that control must not be interpreted solely as lethal control.

"Eradicating long-established entire populations of greys would be very difficult and cause suffering."