The World Health Organization's assembly on Tuesday adopted a resolution to hold an independent investigation into the agency's response to the outbreak of the new coronavirus.

The resolution, drawn up by over 60 signatories, including all member nations of the European Union, Australia and Japan, includes a call for the WHO's continued investigation into the source of the virus. China said Tuesday it backs the resolution.

While WHO Director General Tedros Ghebreyesus has agreed to the inquiry into the international response to COVID-19, deliberations on a proposal by 14 states to invite Taiwan to the World Health Assembly as an observer were postponed.

Although the proposal will be discussed in an assembly later in the year, it is expected to be denied by China, which argues Taiwan's inclusion would violate Beijing's one-China policy.

Meanwhile, U.S. President Donald Trump posted a four-page letter addressed to Tedros on his Twitter account, saying his administration's review of the WHO's response to the viral outbreak has identified concerns including the organization's "alarming lack of independence" from China.

Trump added that if the WHO "does not commit to major substantive improvements within the next 30 days, I will make my temporary freeze of United States funding to the World Health Organization permanent and reconsider our membership in the organization."

The annual conference, shortened to two days from five, is being held via video conferencing this year due to the pandemic. Representatives of member nations usually gather at the organization's headquarters in Geneva, Switzerland.

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