"Action is needed quickly. We do not have time to waste."

This is just a small extract from US President Donald Trump's four-page letter sent to the World Health Organization (WHO) Monday.

Trump threatened to permanently cut funding to organization and also hinted at Washington's possible exit from the agency.

"If the World Health Organization does not commit to major substantive improvements within the next 30 days, I will make my temporary freeze of US funding permanent and reconsider our membership in the organization," Trump wrote to WHO Director-General Tedros Adhanom.

Trump posted the letter on his Twitter account Monday evening, saying it is "is self-explanatory!"

In the letter, Trump announced that his government had already started discussions with Tedros on how to reform the organization.

He also expressed concern at the WHO's "alarming lack of independence from the People's Republic of China" and urged the agency to disassociate itself from the country where the pandemic originated last December.

"The only way forward for the World Health Organization is if it can actually demonstrate independence from China," said Trump.

The US President had on April 14 ordered the suspension of the US' funding to the WHO – the country is the agency's biggest donor – while a review was conducted to assess the WHO's "role in severely mismanaging and covering up the spread of the coronavirus."

In his letter on Monday, Trump said that the review had confirmed many of the serious concerns he had raised last month.

Trump's letter came on the day coronavirus death toll in the US topped 90,000 and the number of confirmed cases crossed 1.5 million making it the worst hit country so far..