Hollywood star Orlando Bloom has backed efforts to save the UK's threatened butterflies by sponsoring a book aimed at helping children engage with the natural world.

Bloom, 34, who has recently become a father, has sponsored Crystal, the Small Miracle, a children's book about butterflies.

The Lord of the Rings actor, who is currently in New Zealand filming The Hobbit: An Unexpected Journey, said: "Butterflies are powerful symbols of the beauty and vulnerability of nature."

Crystal, the Small Miracle, mixes fact and fiction to chart the life story of a butterfly from tiny egg to fully formed butterfly.

The "faction" book was written by Orlando's mother, the celebrated author Sonia Copeland Bloom and is published by wildlife charity Butterfly Conservation.

Orlando, who is married to Australian model Miranda Kerr, added: "I am delighted to back Butterfly Conservation and their efforts to ensure that these wonderful insects are conserved for future generations to enjoy.

"The story of Crystal, the Small Miracle, written by my mother for children everywhere, reflects her own love of butterflies as well as her passion for children to be educated about the insect world in general."

Sonia Copeland Bloom, from Canterbury, Kent, explained: "The transformation of caterpillar to chrysalis and then butterfly is one of nature's greatest miracles.