A special vault has been built in the Arctic to store thousands of seeds, as scientists fear the impact of climate change and prolonged conflicts could have devastating consequences on food crops around the world.

The Global Seed Vault has been built inside a mountain, near the town of Longyearbyen on the remote Svalbard Islands.

It stores thousands of sample seeds from dozens of different countries.

BBC's David Shukman has been given special access to the vault.