US President Donald Trump has again defended the use of hydroxychloroquine to ward off coronavirus, contradicting his own public health officials.
He said the malaria medication was only rejected as a Covid-19 treatment because he had recommended its use.
His remarks come after Twitter banned his eldest son for posting a clip promoting hydroxychloroquine.
There is no evidence the drug can fight the virus, and regulators warn it may cause heart problems.
Last month, the US Food and Drug Administration (FDA) cautioned against using the drug to treat coronavirus patients, following reports of "serious heart rhythm problems" and other health issues.
The FDA also revoked its emergency-use authorisation for the drug to treat Covid-19. The World Health Organization (WHO) says "there is currently no proof" that it is effective as a treatment or prevents Covid-19.
Studies commissioned by the WHO, the US National Institutes of Health and other researchers around the world have found no evidence that hydroxychloroquine - when used with or without the antibiotic azithromycin, as repeatedly recommended by President Trump - helps treat coronavirus.
Hydroxychloroquine was first touted by Mr Trump in March. Two months later he surprised journalists by saying he had begun taking the unproven medication to ward off the virus.