SECURITY for the construction of Oxford's controversial animal research lab will cost an estimated £4.5m.

The figure increases the estimated £20m cost of its construction by more than 20 per cent - and does not include security costs the university could incur after the lab is completed or the cost of policing protests.

Animal rights activists have condemned the costs and pledged to continue the fight against the centre in South Parks Road, even after it is completed.

A spokesman for Oxford University said: "The university has supplied the figure of £4.5m, which is what is expected to be spent on security provision at the site of the biomedical research building up to its completion. We will not break this down further.

"Oxford University is committed to ensuring that all those involved with this project can work and go about their lawful business without their security or safety being compromised."

In 2005, Lord Sainsbury, then Under Secretary of State for Science and Innovation, pledged to help the university with additional costs it would face constructing the laboratory.

A spokesman for the Department of Trade and Industry said: "The Government is working closely with the university and police to ensure that the project continues.

"The facility will replace a range of existing accommodation across Oxford, improving welfare standards for animals and providing world-class facilities for groundbreaking medical research."

Preliminary work on the building started in late 2003, and since construction started in early 2004, animal rights campaign group Speak has held regular demonstrations at the site and in the city centre.

Mel Broughton, a spokesman for Speak, said: "I think it's a shameful waste of money - the health service and other areas of research are crying out for money. Even when the lab is finished we will continue to protest."

University president Alan Strickland said: "It's difficult to put a reasonable price on protecting staff and students, but it would concern me if the university has to bear the full £4.5m cost. The Government cannot expect Oxford's wider teaching and research to suffer in order to get this new facility up and running."

In July 2005, the Animal Liberation Front (ALF) claimed responsibility for an arson attack on Hertford College boathouse, and for an explosive device planted in the Corpus Christi sports pavilion two months later.

In November 2006, the ALF claimed responsibility for another arson attack, against The Queen's College sports pavilion.