The scale of the crisis was obscured by China as the world began grapple with the enormity of the crisis in January.
A senior, former M16 official said the intelligence agencies knew what was “really happening” in China and passed that onto Government ministers, according to The Telegraph.
Recent studies suggest the true number of people infected in China was close to a quarter of a million by mid-February – four times higher than the official figure.
China has also since revised its death toll up by 50 per cent – its official death toll stands at 4,633.
Downing Street continued to use China’s official figures in graphs comparing the scale of outbreaks in different countries – until last week, when it dropped China from the charts altogether because of concerns over the reliability of the data.
A former senior intelligence officer at MI6 said: “The intelligence community would have known what was really happening in China.
“The idea that the UK would have taken Chinese figures at face value is frankly ridiculous.
“If the Chinese are lying, the role of the intelligence community is to know what the real figures might be if they are being hidden.”
A source said: “We didn’t believe these figures coming from China.
“The Government would have been fully aware of the true scale of the virus in China at that time.”
Doubts have also been expressed over the source of the outbreak.
China has insisted that the outbreak began in a Wuhan wet market where live animals are sold for consumption.
But the nearby Wuhan Institute of Virology has been a key source of concern after claims that lax biosecurity may have allowed a disease being examined in the lab to escape.
A Chinese television news report from two years ago shows scientists inside the “emerging viruses group” at the institute failing to wear proper personal protective equipment while studying bats.
US President Donald Trump has said he has seen evidence that the outbreak did not happen come from the wet market and is “confident” China lied about it.
In reports in the US, the president was told at a January 28 briefing that “China was withholding data”.
He had been warned five days earlier that the coronavirus had the potential to “spread globally”.
It is expected that Boris Johnson would have received similar briefings.
Former Attorney General and ex-chair of the Intelligence Select Committee (ISC) Dominic Grieve said MPs needed to investigate what intelligence had been collected on the virus outbreak in China, and what ministers knew.
Mr Grieve said: “The ISC is there to ask questions.”
An intelligence dossier, seen by an Australian newspaper, was shared among the Five Eyes security alliance – US, UK, Canada, Australia and New Zealand – and accused China of covering up the severity of the outbreak from early December 2019.
The dossier said: “Despite evidence of human to human transmission from early December, PRC [Chinese] authorities deny it until January 20.”
It questioned why China imposed bans on people moving around the country, but continued to insist wider international travel bans were unnecessary.
It also suggested China may have lied about the origins of coronavirus – pointing to the concerns surrounding the Wuhan Institute of Virology.
The report said one study lead by scientist Dr Shi Zhengli conducted research into bat-derived coronavirus – with some samples being a 96 per cent genetic match to COVID-19.
Director of the Asia Studies Centre at the Henry Jackson Society, which uncovered the video from the Institute, Matthew Henderson said: “This video adds all the more evidence that the Wuhan Institute of Virology — which was handling lethal new Coronavirus strains — was not observing basic biosecurity.
“Given what we now know about lax biosecurity standards, it is at the very least plausible that human error at a virology lab contributed to the spread of the pandemic.”
He added: “Since Beijing refuses independent access to these sites, their records and their research, why should we think otherwise?”
The Chinese Embassy in Londom said: “The head of the Wuhan Institute of Virology stressed in an interview that the institute is run on a set of strict management rules.
“High-level bioresearch safety labs have sophisticated protective facilities and strict measures to ensure the safety of laboratory staff and protect the environment from contamination.”
The embassy said there was “zero infection” within the institute, adding: “There is no evidence showing the virus came from a lab… Rumour-mongering as well as slander and smear will only damage international solidarity.”