A packet of hydroxychloroquine pills. Gerard Julien/AFP/Getty Images

India has placed a blanket ban on all exports of hydroxychloroquine, just as President Donald Trump called on Indian Prime Minister Narendra Modi to release more of the drug to the United States.

In an official notification issued Saturday, India's Ministry of Commerce and Industry amended a previous order issued last month and effectively banned all export of the drug. It is unclear whether the export ban was made before or after Trump and Modi spoke in a telephone call on Saturday.

“The export of Hydroxychloroquine and formulations made from Hydroxychloroquine, therefore, shall remain prohibited, without any exception,” stated the notification.

Hydroxychloroquine is an anti-malaria drug that some institutions are researching for a possible Covid-19 treatment. Yet there is little reliable evidence that the drug is effective at treating the novel coronavirus.

President Trump, however, has doubled down on the unproven therapy, and at a briefing at the White House on Sunday said:

"They (India) make large amounts of hydroxychloroquine -- very large amounts frankly. And I said -- they had a hold because you know they have 1.5 billion people and they take a lot of it, and I said I would appreciate if they would release the amounts that we ordered and they are giving it serious consideration. But India makes a lot of it.”

In India, the eligible individuals for use of the drug are "Asymptomatic healthcare workers involved in the care of suspected or confirmed cases of Covid-19 and asymptomatic household contacts of people testing positive for Covid-19."

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said there is no "definitive information to be able to make any comment" on whether the drug can be used to treat coronavirus.

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