Oxford University has been granted an injunction to stop animal rights protesters harassing contractors at the site of its £18m animal testing laboratory.

The judgment comes as the university tries to find a replacement for the original contractor, Montpellier, which quit in July after complaining of intimidation.

The High Court ruling on Wednesday extends until further notice the temporary “no harassment zone” granted to the university project in October.

It bans named animal rights activists and groups from coming within 50 yards of the facility, and also of the premises of any contractors, subcontractors and suppliers working on the project.

Protesters are also prohibited from picketing, demonstrating or loitering within 100 yards of the homes of those protected by the order.

John Hood, the vice-chancellor of Oxford University, said that the injunction would offer the project the protection it required.

He said: “We are satisfied that this order strikes a fair balance between the legitimate right to protest and the right of individuals to conduct their lawful business without fear of intimidation and violence.”

Industry sources say the university is still trying to find a firm to replace Montpellier but there is speculation that the government may resort to army engineers to complete the project.