Oxford had become the new focus for animal rights groups

It asked the High Court to extend a 45m "no harassment" zone around its research laboratory, claiming work was stopped because of intimidation.

The university had also requested an injunction against 10 named defendants.

University chiefs had offered to provide a demonstration area opposite the South Parks Road site.

Intimidation or violence

Oxford University Vice-Chancellor, Dr John Hood, said on Wednesday: "As an academic institution, freedom of speech within the law is highly valued.

"By obtaining this injunction, the University of Oxford is not seeking to stifle the views of those groups and individuals with whom we disagree.

"Indeed, 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 or violence."

Work on the construction of the laboratory was forced to stop on 13 July after contractors complained they had been harassed and intimidated by some animal rights activists.

Wide-ranging ban

The injunction creates a 45m exclusion zone - banning picketing, demonstrating or loitering - around the university's buildings and grounds and the property of any of the contractors.

There is also a 91m "no go" area around the homes of the university's members, employees and their families, its shareholders, its contractor employees, shareholders and their families, and anyone who visits the research laboratory.

Taking photographs of such people, their vehicles, and communicating with them in any way is prohibited.

The injunction was imposed upon John Curtin, and the groups Speak Campaigns, Shac (Stop Huntingdon Animal Cruelty) and ALF (Animal Liberation Front).

Proceedings were discontinued against Mel Broughton and Robert Cogswel, of Speak, after they offered legal undertakings not to harass any of the "protected persons" under the order.

The defendants contested the injunction under the 1997 Protection from Harassment Act on the basis that there was no evidence that they were acting unlawfully.

Weekly four-hour demonstrations in the area designated opposite the laboratory site restricted to 25 protesters will continue.

After the hearing, Mr Cogswell criticised the university's stance and argued that it would "restrict people's rights in a democratic society to legally protest".

He said it would "criminalise" the activities of law-abiding citizens.