President Donald Trump has warned India that the US may retaliate if it did not export anti-malarial drug hydroxychloroquine despite his personal request, saying he would be surprised if New Delhi did not relent as it has good relations with Washington.Hydroxychloroquine, an old and inexpensive drug used to treat malaria, is seen as a viable therapeutic solution by President Trump to coronavirus that has so far killed more than 10,000 Americans and infected over 3.6 lakh within weeks.Last week Trump said he has sought help from Prime Minister Narendra Modi to allow the sale of hydroxychloroquine tablets ordered by the US to treat the growing number of coronavirus patients in his country, hours after India banned the export of the anti-malarial drug."I would be surprised if that (not exporting the drug) were his (Prime Minister Modi's) decision. He'd have to tell me that. I spoke to him Sunday morning, called him, and I said we'd appreciate your allowing our supply to come out."If he doesn't allow it to come out, that would be okay, but of course there may be retaliation. Why wouldn't there be?" Trump told reporters during a press briefing at the White House on Monday.His remarks came at a time when both countries are in the grip of the COVID-19 pandemic."I would be surprised if he would, you know, because India does very well with the United States," Trump said.Last month, India imposed a ban on the export on hydroxychloroquine, on which Trump is now banking heavily for the treatment of COVID-19 patients.India has received similar requests from several other countries including its immediate neighbours Sri Lanka and Nepal. India has said that it is reviewing its export ban order.Notably, India's decision to ban the exports of hydroxychloroquine is driven by its desire to take stock of the domestic requirements and ensure that the country has enough in its kitty.Reiterating that for many years, India has been taking advantage of the US on trade, Trump said that he would be surprised if New Delhi was to stop export of hydroxychloroquine to the US.The Indian Council of Medical Research (ICMR) has recommended the anti-malarial drug for those involved in the care of suspected or confirmed cases of the coronavirus and also, for the asymptomatic household contacts of laboratory confirmed cases.On Monday, a senior State Department official said that India has been a significant partner of the US in the pharmaceutical sector and it expects similar cooperation to continue between the economies.“India has long been a significant partner of the United States in the pharmaceutical sector,” Alice G Wells, the Acting Assistant Secretary of State for South and Central Asia, told reporters during a press briefing.The Trump administration has already created a national strategic stockpile of 29 million doses of the malaria drug, anticipating that its test results on more than 1,500 COVID-19 patients in New York is yielding positive results.Global scientists, racing against time to find either a vaccine or a therapeutic cure to the virus, have begun testing hydroxychloroquine and chloroquine as candidates for potential COVID-19 treatments and the FDA last week issued an Emergency Use Authorization for the prescription of the drugs in certain circumstances.In addition to New York, COVID-19 patients in several States are being treated with hydroxychloroquine, including Michigan and Texas.Based on some initial results, the Trump administration is banking heavily on using hydroxychloroquine for the successful treatment of coronavirus.According to Trump, the drug is yielding positive results. If successful, he told reporters that it would be a gift from heaven.In the next several weeks, health experts in the US have projected between 100,000 to 200,000 deaths due to the coronavirus, which due to human-to-human transmission is spreading like a wildfire in the country.