Geneva - The World Health Organization has updated its account of the early stages of the COVID crisis to say it was alerted by its own office in China, and not by China itself, to the first pneumonia cases in Wuhan.

The UN health body has been accused by US President Donald Trump of failing to provide the information needed to stem the pandemic and of being complacent towards Beijing, charges it denies.

On April 9, WHO published an initial timeline of its communications, partly in response to criticism of its early response to the outbreak that has now claimed more than 521,000 lives worldwide.

In that chronology, WHO had said only that the Wuhan municipal health commission in the province of Hubei had on December 31 reported cases of pneumonia. The UN health agency did not however specify who had notified it.

WHO director Tedros Adhanom Ghebreyesus told a press conference on April 20 the first report had come from China, without specifying whether the report had been sent by Chinese authorities or another source.