The role of the Huanan seafood market in Wuhan is also unclear.
"A laboratory origin of the pandemic was considered to be extremely unlikely", the report said.
"It is clear that that the Chinese government has not provided all the data needed and, until they do, firmer conclusions will be hard", he said in a statement.
Last year, an AP investigation found the Chinese government was strictly controlling all research into its origins. The report's release has been repeatedly delayed, raising questions about whether the Chinese side was trying to skew the conclusions to divert blame for the pandemic, according to the AP.
The U.S. government has questioned whether the WHO-convened experts were given enough access to reach a reliable conclusion. "By doing this, isn't the USA trying to exert political pressure on the members of the World Health Organization expert group?" asked Foreign Ministry spokesperson Zhao Lijian.
Next steps The experts suggested the virus might have been introduced through imports to Wuhan of meat from wildlife farms in provinces where bats have been shown to carry similar coronaviruses.
As Britons dipped back into a pre-pandemic life, several experts turned their attention to the origins report.
The report, according to The Telegraph, describes laboratory infection accidents as a "rare" event that occurs in facilities subject to negligence, poor management, and limited biosafety.
"There is no record of viruses closely related to SARS-CoV-2 in any laboratory before December 2019, or genomes that in combination could provide a SARS-CoV-2 genome", it reads.
The WHO did not immediately reply to a query seeking comment, but said the full report by the independent experts would be published on Tuesday at 1400 GMT after member states have been briefed. The mission was never meant to identify the exact natural source of the virus, an endeavour that typical takes years.
In the draft obtained by the AP, the researchers listed four scenarios in order of likelihood for the emergence of the new coronavirus.
They concluded that transmission through a second animal was likely to very likely.
The report meanwhile did not rule out transmission through frozen food - Beijing's favored theory - since the virus appears to be able survive at freezing temperatures, saying that "introduction via cold/ food chain products is considered possible".
The United States expects the WHO-led investigation to require further study of the virus, perhaps including a return visit to China, a senior US official told reporters last week.
It also pointed out that "antibodies to bat coronavirus proteins have been found in humans with close contact to bats". The research - conducted by a team made up of both global and Chinese experts - was aimed at galvanizing efforts to trace the origin of the virus that touched off the worst pandemic in more than a century, as well as its route of transmission to humans and the possible role of an intermediate animal host.
Delays in the publication of the findings, drafted in collaboration with the team's Chinese counterparts, had been blamed on coordination and translation issues, even as a diplomatic tug-of-war raged in the background over the report's contents. It wasn't clear whether the report might still be changed prior to release, though the diplomat said it was the final version.
"We were surprised to find that the specific interaction between ACE2 glycans and the SARS-CoV-2 spike protein is what makes the separation of the virus from cells so hard", says Im, who is a professor of bioengineering, computer science, chemistry and biological sciences, as well as the Presidential Endowed Chair in Health, Science and Engineering at Lehigh.
Ever Given Ship In Suez Canal Is Re Floated With Egyptian Help
But Rabie on Saturday acknowledged that "technical or human errors" led to the Panama-registered super container ship's grounding. Some shippers rerouted their cargoes around the Cape of Good Hope, adding up to two weeks to journeys and extra fuel costs.
Myanmar Military Opens Fire on Funeral
Nations including Germany and the U.S. jointly decried the military violence which resulted in over 100 deaths in one day. They added that "the global community has a responsibility to protect the people of Myanmar from atrocity crimes".
Suez Canal ship 'now moving,' owner says
Crews from Egypt and around the world have been working nonstop to try to refloat the ship, but previous efforts have failed. The pair have a combined pulling capacity of around 400 tons, said spokesman Martijn Schuttevaer.