Editor's Note: This story was published on April 21, 2020. It was updated on May 19 after President Donald Trump wrote to the World Health Organization threatening to permanently withdraw US funding.

(CNN) President Donald Trump is escalating his threats against the World Health Organization, telling the agency he will permanently pull US funding if it does not "commit to major substantive improvements in the next 30 days."

Trump challenged the WHO to "demonstrate independence from China," in the letter that he posted on Twitter late Monday.

In April, Trump repeatedly criticized the WHO for being "China-centric" and failing to "objectively assess the situation on the ground and to call out China's lack of transparency" as the coronavirus death toll increases globally.

Trump's heightened rhetoric comes as he and his administration are facing scrutiny over their own handling of the pandemic, with early missteps that included downplaying the threat the virus posed and delays and shortages in coronavirus testing.

Although Trump has recently expressed some displeasure with China, his tough comments of late are a far cry from his past statements on the nation and its leader, Xi Jinping, whom he praised for his transparency and management of the outbreak.

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