Donald Trump says other countries had provided great reports on the effectiveness of hydroxychloroquine.
Hydroxychloroquine, a malaria drug, has been used for the treatment of the deadly coronavirus.
However, scientists have recently said it is not effective and may make COVID-19 worse for patients.
Reuters reports that Trump is complaining that U.S. agencies have failed to grasp its benefit.
His remarks came hours after the FDA revoked its emergency use authorization for COVID-19 treatment.
Trump has frequently praised the drug’s usefulness for staving off the disease in recent weeks.