US President Donald Trump's decision to halt payments to the UN's health agency amid the novel coronavirus pandemic continues to split opinions between loyalists and health experts who question its wisdom.

In so doing Trump accused the World Health Organization (WHO) of "severely mismanaging and covering up the spread of the coronavirus" during a news briefing Tuesday, and said the halt in US payments would continue while a probe is carried out.

When Trump foreshadowed the move last week he accused the health body of being "China-centric," maintaining it had been the source of poor information for governments worldwide, particularly its opposition to countries closing their borders to China after the virus emerged there in December.

In the four months that have since passed, more than 2 million people worldwide have tested positive for COVID-19, the respiratory disease it causes, while over 133,000 have died, according to data from Johns Hopkins University.

Senator Lindsey Graham, a staunch Trump ally, praised the decision to suspend funding, accusing WHO's leadership of having "proven to be incompetent and shown overwhelming evidence of China bias.

"If someone like Bill Gates were in charge of the WHO I would gladly support increased funding, but I have lost all confidence in the current WHO leadership and capabilities," he wrote on Twitter.

The South Carolina senator was referring to the tech billionaire turned philanthropist who earlier issued a sharp rebuke of Trump's decision.

"Halting funding for the World Health Organization during a world health crisis is as dangerous as it sounds," Gates, who with his wife Melinda runs the global health-focused Gates Foundation, wrote on Twitter. "Their work is slowing the spread of COVID-19 and if that work is stopped no other organization can replace them. The world needs @WHO now more than ever."

Some within Trump's administration have also voiced support for the WHO following his announcement.

Robert Redfield, the director of the U.S. Centers for Disease Control and Prevention (CDC), declined to criticize the WHO during morning talk show, despite being repeatedly pressed earlier Wednesday, hailing the body as having "very productive" ties with the CDC that continue through the outbreak.

"I'd like to do the postmortem once we get through it together," he said on Good Morning America, deflecting a question on whether the WHO failed in its mission.