The BBC's Andrew Bomford reports on the protest

About 250 protesters have gathered at the Shamrock GB farm in West Sussex - the UK's biggest importer of monkeys for experimental purposes - in support of Barry Horne who is in a critical condition at a York hospital.

Police say the demonstration has been noisy but non-violent.

Horne, 46, has not eaten since 6 October. He is on hunger strike in an attempt to force the government to set up a royal commission on animal vivisection.

Shamrock GB: Imports monkeys for scientific tests

The protest by supporters from the pressure group Save the Shamrock Monkeys is taking place outside a farm in the West Sussex village of Small Dole.

The group says monkeys imported from Mauritius, the Philippines and China are held at the farm before being distributed to scientific research institutes around the country.

Spokeswoman Kerry Williams said: "We protest in solidarity with Barry Horne against the evil vivisection industry. Our campaign will continue until Shamrock closes."

Horne was jailed last year for a firebombing campaign against a string of shops that is estimated to have caused damage worth £3m.

The judge who sentenced him to 18 years for arson described him as an "urban terrorist".

No to 'blackmail'

Horne was transferred to hospital on 24 November and he may already be beyond the stage where it is possible for him to recover even if he decides to end his protest.

He has issued instructions ruling out force-feeding should he lapse into a coma.

The Home Office announced an immediate ban on vivisection for cosmetic purposes last week, but insisted that it was "not prepared to allow policy to be dictated by blackmail".