Intelligence agencies in the US have further fuelled the theory Covid-19 leaked from a Wuhan lab following the release of a declassified report.
The Office of the US Director of National Intelligence (ODNI) said in the report that a lab leak at the Wuhan Institute of Virology was a hypotheses as plausible as a a natural transmission to humans from animals.
Its analysts differed in opinions which was more likely and feared a definitive assessment may never arise due to the lack of information at hand from China.
The report issued on Friday (local time) is an update of a 90-day review that President Joe Biden's administration released in August, amid intense political infighting over how much to blame China for the effects of the global pandemic rather than governments that may not have moved quickly enough to protect citizens.
China predictably criticised the report hours after its release.
"The US moves of relying on its intelligence apparatus instead of scientists to trace the origins of COVID-19 is a complete political farce," Liu Pengyu, a spokesperson for the Chinese embassy in Washington, said in an emailed statement.
"It will only undermine science-based origins study and hinder the global effort of finding the source of the virus."
Former Republican President Donald Trump - who lost his bid for re-election as the deadly pandemic ravaged the US economy - and many of his supporters referred to Covid-19 as the "China virus."
In September, Mr Trump said classified evidence suggested it was 95 per cent likely the virus came from the Wuhan Institute of Virology.
Spy agencies divided over source of virus
Some US spy agencies had strongly favoured the explanation that the virus originated in nature. But there has been little corroboration and over recent months the virus has spread widely and naturally among wild animals.
The ODNI report said four US spy agencies and a multi-agency body have "low confidence" that Covid originated with an infected animal or a related virus.
But one agency said it had "moderate confidence" that the first human COVID-19 infection most likely was the result of a laboratory accident, probably involving experimentation or animal handling by the Wuhan Institute of Virology.
US spy agencies believe they will not be able to produce a more definitive explanation for the origin of Covid without new information demonstrating that the virus took a specific pathway from animals to humans or that a Wuhan laboratory was handling the virus or a related virus before it surfaced.
The report said US agencies and the global scientific community lacked "clinical samples or a complete understanding of epidemiological data from the earliest Covid cases" and said it could revisit this inconclusive finding if more evidence surfaces.
China has faced international criticism for failing to cooperate more fully in investigations of Covid's origins.
The embassy statement also dismissed that criticism.
"We have been supporting science-based efforts on origins tracing, and will continue to stay actively engaged. That said, we firmly oppose attempts to politicise this issue," it said.
China has repeatedly refuted claims the virus originated in the lab and has responded furiously to such claims.
Its foreign ministry has routinely pointed the finger instead at the US and other European countries, suggesting the virus originated earlier in 2019 overseas.
Initially criticised for his soft approach with China, World Health Organisation chief Tedros Adhanom Ghebreyesus surprisingly questioned the findings of a joint mission into the origins of the virus earlier this year calling on more to be done to investigate the lab leak theory and called for a new team of experts in the process.
The US report also dismissed suggestions that the coronavirus originated as a bioweapon, saying proponents of this theory "do not have direct access to the Wuhan Institute of Virology" and have been accused of spreading disinformation.
- With Reuters
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