Coronavirus: US President Donald Trump said he spoke to PM Modi on Sunday.

Highlights Hydroxychloroquine is a key drug used in the treatment of COVID-19

The centre announced a hold on export of hydroxychloroquine on March 25

India is one of the world's largest manufacturers of the medicine

US President Donald Trump has said "there may be retaliation" if India does not agree to export hydroxychloroquine, a key anti-malaria drug believed by many to be effective in the treatment of coronavirus. His remarks come nearly two weeks after the government banned export of the drug as experts test its efficacy in helping treat COVID-19 patients.

"I would be surprised if he (Prime Minister Narendra Modi) would, you know, because India does very well with the United States," Mr Trump said at a White House press briefing on Monday, when a reporter asked whether he was worried about "retaliation to the US ban on export of medical goods" from India.

"I don't like that decision, I didn't hear that that was his decision. I know that he stopped it for other countries. I spoke to him yesterday, we had a very good talk and we'll see whether or not that's his... For many years, they've been taken advantage of the United States on trade. So I would be surprised if that were his decision. He'd have to tell me that. I spoke to him Sunday morning, called him, and I said, we'd appreciate you allowing our supply to come out. If he doesn't allow it to come out. That would be OK. But of course, there may be retaliation. Why wouldn't there be," the US President said.

Trump has described hydroxychloroquine as a "game-changer" though it is yet to be established as an effective cure for COVID-19.

Last month, the Indian Council of Medical Research or ICMR had recommended the use of hydroxychloroquine for treating healthcare workers serving coronavirus patients.

In a notification on March 25, the government announced a hold on the medicine's export, adding that it would be allowed only on "case-to case basis" on humanitarian grounds. India has reported over 4,000 coronavirus patients so far and more than 100 deaths.

This morning, however, the government said that key drugs linked to COVID-19 cure will be supplied to "nations that have been badly affected" by the pandemic.

"In view of the humanitarian aspects of the pandemic, it has been decided that India would licence paracetamol and Hydroxychloroquine in appropriate quantities to all our neighbouring countries who are dependent on our capabilities. We will also be supplying these essential drugs to some nations who have been particularly badly affected by the pandemic. We would therefore discourage any speculation in this regard or any attempts to politicise the matter," Foreign Ministry spokesperson Anurag Srivastava said.

Currently, the US has the most number of coronavirus cases in the world. The coronavirus death count has crossed 10,000-mark in US; over 366,000 have contracted infection so far.

Last week, the US Food and Drug Administration (FDA) issued an Emergency Use Authorization or EUA to permit the emergency use of hydroxychloroquine sulfate supplied from the national stockpile to treat adult and adolescent COVID-19 patients who weigh 50 kg or more and are hospitalised, according to an official statement.