"It is my belief that the WHO must be supported, as it is absolutely critical to the world's efforts to win the war against COVID-19," Guterres said in a statement on Tuesday cited by Xinhua news agency.
It is "not the time to reduce the resources for the operations of the WHO or any other humtarian orgsation in the fight against the virus," he added.
Trump said that the funding would be suspended while officials would conduct a review "to assess the WHO's role in severely mismanaging and covering up the spread of the coronavirus" that emerged in China late last year.
Guterres noted that "now is the time for unity and for the international community to work together in solidarity to stop this virus and its shattering consequences."
"Once we have finally turned the page on this epidemic, there must be a time to look back fully to understand how such a disease emerged and spread its devastation so quickly across the globe, and how all those involved reacted to the crisis," the UN chief said, adding that "the lessons learned will be essential to effectively address similar challenges, as they may arise in the future."
Trump has been very critical of the WHO stating that the orgsation was aware of the dangers of the coronavirus months before it took action.
The United States is the worst-hit country from the coronavirus. The virus has killed over 25,000 people in the country since the outbreak. There are at least 5,94,207 cases of coronavirus in the country, marking the highest number of cases among all countries in the world.
The WHO has been criticised for its role in tackling the health crisis brought upon by the pandemic that has infected around 1.9 million people and killed 126,019 across the world.
( With inputs from ANI )