U.S. President Donald Trump announced on Tuesday a freeze in funding for the World Health Organization as the administration conducts a 60- to 90-day review of the organization’s response to the coronavirus pandemic.

Trump has criticized the WHO for being “China-centric,” covering up the spread of the virus, not supporting necessary travel bans and causing a “20-fold” increase in global cases because of its delayed investigation into early reports from China.

In February, when Trump restricted some travel from China, the WHO sent out an advisory against the application of travel restrictions on countries experiencing COVID-19 outbreaks. “In general, evidence shows that restricting the movement of people and goods during public health emergencies is ineffective in most situations and may divert resources from other interventions. Furthermore, restrictions may interrupt needed aid and technical support, may disrupt businesses, and may have negative social and economic effects on the affected countries,” advised the WHO.

The WHO, the U.S. president claimed, should have critiqued China’s “lack of transparency,” where it instead praised China for its lockdown measures and the government’s “transparency” in dealing with the virus. The WHO has been widely criticized for obfuscating China’s culpability in misinformation and allowing the coronavirus to spread in the early stages of the pandemic.

“The WHO failed in its basic duty and must be held accountable,” Trump said in a news briefing.

In response to his announcement, U.N. Secretary General António Guterres said that now is not the time to end support for the WHO, calling the organization “absolutely critical” to combating worldwide spread of the virus.

A review, he said, would be more appropriate “once we have finally turned the page on this pandemic.”

Last year, according to a WHO budget document, the U.S. contribution totaled more than $400 million of its $4.4 billion budget.