Animal rights campaigners have held a protest at the site of an £18m animal testing centre in Oxfordshire.
Hundreds of protesters march through the centre of Oxford
About 500 people took part in the peaceful march to Oxford University's new centre in South Parks Road, according to a BBC journalist.
Activist Joan Court, 85, who recently took part in a 48-hour hunger strike over the move, was among the speakers.
The university has said the centre will replace existing sites and "does not mean an increase in animal tests".
Organiser Robert Cogswell, of the pressure group SPEAK - Stop Primate Experiments at Cambridge - which was founded in July 2004, said: "It was a great turn out and it was peaceful.
"It is a great victory for us that the main building contractor Walter Lilly & Co has pulled out.
"We will be legally targeting the next building contractor and then will we will identify the sub-contractors being employed by the new main contractor.
"We want to send a clear message that this campaign will continue and intensify legally."
The demonstrators gathered at Broad Street in the centre of the city, before marching to the site at 1330 BST.
Oxford MP, Dr Evan Harris said: "Given this research is necessary, it is clearly in everyone's interest, including those of the research animals, that state-of-the art facilities - such as the one being built in Oxford - are used.
"Everyone has the right to protest but these protesters should be seeking a change in government policy and should therefore be lobbying Westminster and not Oxford University."
The action on Saturday follows news that the Army could be brought in to help the university finish work on the site.
Lord Sainsbury, the science minister, is reported to be considering putting troops on standby to help deliveries. They would not be involved in security.
Neither the university nor Walter Lilly's parent company, Montpellier PLC, gave reasons for the builder's withdrawal.