Donald Trump has enthusiastically told his 80 million Twitter followers he is behind the Australian-backed push for an independent COVID-19 inquiry.
The US president retweeted an AAP Newswire/SBS story on Monday detailing how 116 countries are supporting the probe.
"We are with them!" the president wrote above a link to the story.
Trump's tweet will likely add to rising tensions between the US and China.
China is slapping punitive tariffs of more than 80 per cent on Australian barley imports.
The tariffs come one week after China imposed a ban on meat imports from four Australian processing plants.
Australian Prime Minister Scott Morrison led global calls for the COVID-19 probe and a resolution is expected to be approved in the World Health Assembly in Geneva.
The African Group's 54 member states will co-sponsor the motion, joining 62 other countries including New Zealand, the European Union's 27 members, Russia, Indonesia, India, Japan, Britain and Canada.
The draft resolution does not mention China, but calls for an impartial, independent and comprehensive evaluation of the international response to the pandemic.
Trump and US Secretary of State Mike Pompeo have ramped up public criticism of China's response to the COVID-19 outbreak.
Pompeo said there was a "significant amount of evidence" the virus originated from a laboratory in Wuhan, China.
Adding to China-Australia-US tensions, the Royal Australian Navy joined the US Navy for exercises in the South China Sea last month.
The US trumpeted the exercises as proof both nations have the "same interest in ensuring freedom of navigation".
Pompeo on Monday also condemned Taiwan's exclusion from the World Health Assembly.
The US and Australia supported Taiwan attending as an observer, despite China's opposition.
"No one disputes that Taiwan has mounted one of the world's most successful efforts to contain the pandemic to date, despite its close proximity to the original outbreak in Wuhan, China," Pompeo said.
"This should not be a surprise.
"Transparent, vibrant, and innovative democracies like Taiwan always respond faster and more effectively to pandemics than do authoritarian regimes."
Australian Associated Press
