Tony Blair has criticised the "anti-science fashion" in Britain, pledging not to let protestors stop medical and economic advances.

In an interview with the Times, to be published in full on Tuesday, the prime minister says it is "time to speak up for science" and warns that animal welfare activists and environmentalists risk stopping projects that could save lives.

"Some of these protests have been completely over the top," he tells the newspaper.

"There are huge challenges and opportunities we have to face up to. It is time to defend science, to make clear that the government is not going to allow misguided protests against science to get in the way of confronting the challenges of making the most of our opportunities."