Mr Trump also pledged on Friday evening to scrap Us funding for the Wuhan institute.

Meanwhile, Us secretary of state Mike Pompeo has demanded that Beijing ‘come clean’ over whether the virus had leaked from the lab. He said: ‘There is still lots to learn.

The US government is work-ing diligently to figure it out.’

He added that one of the best ways that China could find to co-operate would be to ‘let the world in and let the world’s scientists know exactly how this came to be, exactly how this virus began to spread’.

Suspicions of a Chinese cover-up increased further after the Washington Post reported that US diplomats in Beijing had written cables about the Wuhan laboratory in 2018, warning the state Department that ‘the lab’s work on bat coronaviruses and their potential human transmission represented a risk of a new SARs-like pandemic’.

US intelligence sources say that shortly after the coronavirus outbreak began, officials at the lab destroyed samples of the virus, erased early reports and sup-pressed academic papers – and then tried to pin the blame on Wuhan’s wet market, where wild animals are sold for consumption.

The sources believe that ‘Patient Zero’ was an intern at the lab, who spread the virus into the local population after infecting her boyfriend.

One source described it as ‘the costliest government cover-up of all time’.

After initially accepting the wet market theory, intelligence officials in the US, Britain and Canada are increasingly focusing on the Wuhan institute, not least because of the level of coincidence required for the bats in Yunnan to have infected animals in Wuhan, which then passed it on to humans.

Following a video meeting of the G7 nations on Thursday, French President Emmanuel Macron said: ‘There are clearly things that have happened that we don’t know about.’

The World Health Organisation, which faces allegations of complicity with Beijing over the pandemic, quickly accepted and propagated the wildlife market theory.

Although British Government sources say that the evidence suggests that the virus was ‘zoonotic’ – originating from an animal – that is still compatible with the theory that it first passed to humans as a result of an accident by scientists studying it in a laboratory.

However, one political source said that there was ‘growing scientific curiosity’ over the symptoms of a marked loss of taste and smell in many victims of Covid-19.

‘This might – only might – indicate a level of human interference,’ the source said.

Beijing insists that the fact that the country’s primary virology institute is based in the city at the centre of the outbreak is just a coincidence, dismissing links to the laboratory as ‘baseless conspiracy theories’.

In a letter to The Mail on Sunday, a Chinese Embassy spokeswoman says: ‘There has never been any cover-up, nor was a cover-up ever allowed to happen.

The relatively low Covid-19 death toll in China proves that the containment measures are effective. strict lockdown measures have effectively slowed down the spread of the virus and minimised the cases of infection. (Click to Source)