US president Joe Biden has poured fuel on the fire raging around the true origins of the coronavirus pandemic, giving his intelligence agencies a 90-day mandate to uncover fresh evidence.
Taking aim at China, Mr Biden said "specific" questions needed to be answered by the country, which has been accused of withholding key data related to the early days of the global Covid-19 outbreak.
In a statement that will no doubt rankle Beijing, Mr Biden called for further investigation into the pandemic's origins on Wednesday (local time).
He said US intelligence agencies have "coalesced around" two different scenarios, and said they have low confidence in their current conclusions. According to the president, US intelligence remains divided on which theory is most likely.
The first is whether it came from human contact with an infected animal while the other theory posits the virus escaped from a lab in Wuhan.
Two agencies lean toward the animal link and “one leans more toward” the lab theory, Mr Biden said.
"I have now asked the Intelligence Community to redouble their efforts to collect and analyse information that could bring us closer to a definitive conclusion, and to report back to me in 90 days,"he said.
"As part of that report, I have asked for areas of further inquiry that may be required, including specific questions for China."
After months of minimising the possibility the virus escaped from a lab, suggesting it was a fringe theory, the Biden administration has now moved to a more agnostic position on the matter.
He called on China to cooperate with an ongoing push by the US and other nations to better understand the origins of Covid-19, months after WHO investigators travelled to China for that purpose.
"The United States will also keep working with like-minded partners around the world to press China to participate in a full, transparent, evidence-based international investigation and to provide access to all relevant data and evidence," he said.
It comes just days after The Wall Street Journal revealed, citing a US intelligence report, three researchers from the Wuhan Institute of Virology were sick enough to seek hospital care in November 2019.
The renewed focus on the lab theory has already enraged China, with Yuan Zhiming, director of the institute's Wuhan National Biosafety Laboratory, saying the WSJ report was "a complete lie".
Australia backs Biden's new push on virus origins
Australia's relations with China began a steady decline last yer after calling for an investigation into the pandemic's origins. Unsurprisingly, the Federal Government has backed Joe Biden's calls for a fresh investigation.
Foreign Minister Marise Payne welcomed the White House statement but would not be drawn into revealing whether Australian intelligence agencies held a view.
"We will continue to work with our international partners including the United States, with whom we share concerns on this," she told ABC radio.
"The most important thing is that we are able to provide for the international community an assurance that a pandemic of this nature can't happen again because we do understand where it came from and how it happened, and that we do ensure we're all better prepared."
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