WASHINGTON (AP) — In a clash of gut instinct versus science, President Donald Trump and the government’s top infectious disease expert, Dr. Anthony Fauci, are politely but publicly sparing over whether a malaria drug would work to treat people with coronavirus disease.

Trump is clinging to his feeling that a malaria drug widely available could be the answer-in-waiting to an outbreak spreading around the nation, shutting down major parts of the economy, and posing the biggest challenge he has faced as president. Calmly and quietly, Fauci insists the science is not yet there to validate Trump’s hope. Neither man directly challenged the other.

The extraordinary scene played out on national television both Friday and Saturday during White House briefings on the outbreak. Anxious for answers, Americans heard conflicting views.

Reporters asked both men — first Fauci, then Trump — if a malaria drug called hydroxychloroquine could be used to prevent COVID-19, the disease caused by the virus. A day earlier, when Fauci wasn’t with him at that briefing, Trump had called attention to the drug.

Friday, Fauci took the reporter’s question and got right to the point. “No,” he said. “The answer … is no.

“The information that you’re referring to specifically is anecdotal,” Fauci added firmly. “It was not done in a controlled clinical trial, so you really can’t make any definitive statement about it.”

Hydroxychloroquine and a similar drug — chloroquine — are sold around the world under a variety of brand and generic names. They can be prescribed off-label by doctors in the United States. They may interfere with the coronavirus being able to enter cells, and some scientists have reported possible encouraging signs in test-tube and other small studies.

Fauci on Friday went on to explain the Food and Drug Administration is looking for a way to make the drug available for emergency use but in a manner that gives the government data about whether it’s safe and effective. Fauci is director of the National Institute of Allergy and Infectious Diseases at NIH and in more than 30 years has handled HIV, SARS, MERS, Ebola and now the new coronavirus.

Currently, no medicine has been specifically approved for treating COVID-19.

But Trump stuck to what his gut was telling him. As the two men took turns at the podium, Trump said he disagreed with the notion there is no magic drug for the coronavirus disease. “Maybe and maybe not, “ he said. “Maybe there is, maybe there isn’t. We have to see.”

That same mixed-message dynamic was on display during Saturday’s White House briefing — this time with both men publicly acknowledging their clashing stances. Before the briefing, Trump tweeted about a preliminary French study suggesting hydroxychloroquine plus azithromycin, a common antibiotic, might be an effective treatment for COVID-19. During the briefing, Trump doubled down on his support for the malaria drug, saying it would be distributed for use while Fauci remained respectfully skeptical.