Citing a ruling adopted after a meeting of France's high public health council, Veran said the drug could not be used to treat milder cases of the illness.
Some researchers have said chloroquine shows great promise as a treatment, though scientists have agreed that more trials are needed to determine if the drug is really effective and safe.
“The high council recommends not to use this treatment… with the exception of grave cases, hospitalised, on the basis of a decision taken by doctors and under strict surveillance,” Veran told reporters.
President Donald Trump has said the US is fast-tracking chloroquine for use as a treatment but other voices have urged prudence over its effectiveness.
Experts are divided over whether the drugs are suitable though, having undergone only the briefest of clinical trials.
“We're going to be able to make that drug available almost immediately, and that's where the (Food and Drug Administration) has been so great,” Trump told reporters, referring to both antimalarials.
“They've gone through the approval process — it's been approved. They took it down from many, many months to immediate. So we're going to be able to make that drug available by prescription.”
“As an example, many Americans have read studies and heard media reports about this drug chloroquine, which is an anti-malarial drug.
“It's already approved, as the president said, for the treatment of malaria as well as an arthritis condition.
“That's a drug that the president directed us to take a closer look at, as to whether an expanded use approach to that could be done to actually see if that benefits patients.”
Chloroquine is a synthetic form of quinine, which has been used to treat malaria since the 1940s. Hydroxychloroquine shares a similar mechanism of action but is less toxic.
French drug maker Sanofi on Wednesday said it stood ready to offer the French government millions of doses of hydroxychloroquine, sold under its brand name Plaquenil, in light of a “promising” study carried out by Didier Raoult (pictured) of the IHU Mediterranee Infection in Marseille.
Raoult reported this week that after treating 24 patients for six days with Plaquenil, the virus had disappeared in all but a quarter of them. The research has not yet been peer reviewed and published.
Last week Swiss laboratory Novartis offered to make available up to 130 million doses of anti-malarial drug chloroquine, which is considered a potential efficient treatment for the coronavirus.
Pharmaceutical industry executives say they expect it will take 12 to 18 months to roll out a vaccine and jointly pledge to make it available worldwide based on need.
Authorities were alarmed last week when a message circulating on the popular WhatsApp messaging service recommended people to take a dangerously high dose of anti-malaria drug chloroquine to treat COVID-19.