US President Donald Trump has slammed the World Health Organisation's response to the coronavirus outbreak in a letter threatening a permanent freeze on US funding to the body. He said the international agency must demonstrate “independence from China,” and enact sweeping reforms within 30 days to secure a reinstatement of US funding, according to a letter the president posted on Twitter on Monday. “If the World Health Organisation 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 Organisation permanent and reconsider our membership in the organisation,” Mr Trump wrote in the letter to WHO Director General Tedros Adhanom Ghebreyesus. In a tweet accompanying a copy of the letter, Mr Trump called it “self-explanatory.” Mr Trump already made the decision to temporarily stop funding to the WHO on April 14, accusing the group of being too supportive of China. He has also repeatedly accused the UN health body of mismanagement of the crisis, a claim repeated in the letter, which included bullet points laying out his dissatisfaction. The WHO did not give an immediate reaction to the letter, but spokeswoman Fadela Chaib noted that she had seen the letter. “I don’t have any reaction, we have been busy trying to finalise our agenda for the World Health Assembly,” she said, referring to health agency’s annual meeting, which has been shortened this year because of the Covid-19 outbreak and was set to end later Tuesday. “I am sure in the course of the day we will have more clarity and reaction to this letter,” she told reporters at a regular UN briefing in Geneva. Earlier in the day, the WHO said it would launch an independent review of the response to the coronavirus pandemic. During a virtual assembly, Tedros acknowledged there had been shortcomings and told the assembly he welcomed calls for a review. The European Union backed the WHO and multilateral efforts to fight the coronavirus on Tuesday after Trump's comments. "This is the time for solidarity, not the time for finger pointing or for undermining multilateral co-operation," European foreign affairs spokeswoman Virginie Battu-Henriksson told reporters. Half of the WHO's funding is made up of annual donations by member states, and topped up by voluntary donations and funding from other bodies. The US has contributed about 20 per cent of the WHO's overall budget over the past two years.