A former MI6 chief claims the West has been naive in trusting China to come clean over the origins of Covid-19.
If any evidence exists that a lab leak in Wuhan caused the pandemic it would probably have been destroyed by China, the former head of Britain's MI6 has said.
Sir Richard Dearlove, who headed the secret intelligence service between 1999 and 2004, said it would be difficult to prove that the Wuhan Institute of Virology was working on "gain of function" experiments to make a natural coronavirus that would be more deadly to humans.
He said that the West had been naive in its trust of China, which had infiltrated scientific institutions and journals in Britain and beyond.
Speaking to Allison Pearson on The Daily Telegraph's Planet Normal podcast, Sir Richard said it was possible that scientists who wanted to speak out about the experiments had been "silenced".
"The People's Republic of China is a pretty terrifying regime and does some things we consider unacceptable and extreme in silencing opposition to the official line of the government," he said.
"We don't know that's what's happened, but a lot of data have probably been destroyed or made to disappear so it's going to be difficult to prove definitely the case for a 'gain of function chimera' being the cause of the pandemic.
"This is why scientific analysis is now so important, because although that can't prove the case 100 per cent, the thorough biochemical analysis puts the weight of evidence to this being a man-made lab experiment - a natural virus that has been enhanced."
Last week President Joe Biden ordered his intelligence officials to "redouble" their efforts to identify the origins of Covid-19 and report back within 90 days. British intelligence officials are also helping the Americans in establishing whether the pandemic was caused by a lab leak and several eminent scientists have now called for a major inquiry that includes researchers who worked on experiments with Wuhan scientists.
Sir Richard, who has long questioned the natural origins of coronavirus, said he had received "a lot of stick" for his beliefs, but people were beginning to take the issue seriously.
"I do feel a sense of vindication," he said. "There was some extraordinary behaviour in the scientific community which successfully shut down any debate. I would almost call it academic bullying.
"The whole argument has shifted - China was originally let off the hook. I think the problem was the style of the Trump regime - a lot of people understandably found it hard to go along with his more outlandish allegations.
"In the end it's going to boil down to scientific evidence because the data is no longer available unless some courageous Chinese individual, probably a scientist, comes forward.
"Some of the things that were said by George Osborne and David Cameron about our relationship with China - how we were going to have this privileged position - I was staggered at the time by the sheer naivety that they could develop a relationship with China without understanding they were dealing with a communist dictatorship, and one that has its own strategic agenda.
"This is a really important issue and has massive far-reaching implications. If the outcome is likely to be that serious, which personally I think it will be, I can't see China agreeing to pay reparations, and I'm not sure what our future relationship with China is going to be."
Sir Richard said an inquiry into whether the virus leaked from a lab should not be left to the World Health Organisation, which has been criticised for failing to look rigorously into the issue. "The WHO looks like a lost cause and that should not be the agency to deliver material which gives us a clear understanding of what the hell happened," he added.