"We have not received any data or specific evidence from the United States government relating to the purported origin of the virus -- so from our perspective, this remains speculative," the UN health agency’s emergencies director Michael Ryan said.
Trump claims to have proof the new coronavirus (COVID-19) outbreak started in a laboratory in the Chinese city of Wuhan.
Last month, the US president halted funding to the World Health Organisation after he accused the UN boy of initially downplaying the seriousness of the outbreak to “shield China.”
US Secretary of State Mike Pompeo doubled down on the assertion that the outbreak originated from the Wuhan Institute of Virology.
"I can tell you that there is a significant amount of evidence that this came from that laboratory in Wuhan," Pompeo told ABC News on Sunday.
China has vehemently denied suggestions the lab was the source.
The WHO emergencies director said, "Like any evidence-based organisation, we would be very willing to receive any information that purports to the origin of the virus." Ryan stressed that this was "a very important piece of public health information for future control.
"If that data and evidence is available, then it will be for the United States government to decide whether and when it can be shared, but it is difficult for the WHO to operate in an information vacuum in that regard," he added.
Scientists have condemned conspiracy theories about the Chinese laboratory, saying the new coronavirus jumped from animals to humans, emerging in China late last year, possibly from a market in Wuhan selling exotic animals for meat.
Top US infectious disease expert Anthony Fauci echoed the WHO's statement, saying that, "If you look at the evolution of the virus in bats and what's out there now, (the scientific evidence) is very, very strongly leaning toward this could not have been artificially or deliberately manipulated."
"Everything about the stepwise evolution over time strongly indicates that (this virus) evolved in nature and then jumped species," he said.
Intelligence assessment contradicts Trump, Pompeo’s claim
Intel shared among US allies indicated it is "highly unlikely" that the coronavirus outbreak was spread as a result of an accident in a laboratory but rather originated in a Chinese market.
"It is highly likely it was naturally occurring and that the human infection was from natural human and animal interaction," an official from the Five Eyes intelligence-sharing coalition said.
The Five Eyes alliance is made up of the United States, United Kingdom, Canada, Australia and New Zealand.
A source from the Five Eyes nation said that "clearly the market is where the new coronavirus exploded from," but how the virus got to the market remains unclear.
China's state-owned Global Times newspaper slammed Pompeo’s Wuhan lab claim, saying that the former CIA director had "stunned the world with groundless accusations."
"Since Pompeo said his claims are supported by 'enormous evidence,' then he should present this so-called evidence to the world, and especially to the American public who he continually tries to fool," Global Times said.
As the war of words escalates between Washington and Beijing over the coronavirus pandemic, critics say the Trump administration has ramped up efforts to blame China for the global outbreak as it faces growing criticism at home for its own handling of the pandemic.
Nearly 70,000 people died of the coronavirus in the US, and 1,180,634 virus cases were recorded as of early Tuesday morning, according to Johns Hopkins University.