Donald Trump noted that this drug has been successfully used in the fight against malaria.
"There's a real chance that it could have a tremendous impact, it would be a gift from God; if that worked it would be a big game changer," Trump said.
Trump added that the death rate from coronavirus in the US will be below 1%. According to him, "this is a significant factor".
Earlier, Donald Trump said that drug trials to test coronavirus treatments will begin in New York state on Tuesday.
In turn, many scientists including Anthony Fauci, the United States' leading infectious disease expert, have advised the public to stay cautious until larger clinical trials validate the smaller studies.
Earlier, French scientists have reported successful clinical trials of a combination of two existing drugs - Hydroxychloroquine and azithromycin - against the new SARS-CoV-2 coronavirus.
According to the Johns Hopkins University, the United States has almost 44,000 coronavirus cases and 560 deaths.