Travelers pass through Salt Lake City International Airport, Friday, Dec. 24, 2021, in Salt Lake City.
CNN  — 

The US government should consider requiring people to be vaccinated to fly domestically, Dr. Anthony Fauci said Monday.

The federal government currently requires noncitizens coming to the United States by air to be fully vaccinated. Fauci said it’s worth considering broadening those requirements.

“You’ve got to ask yourself why it is you’re making that requirement,” Fauci told MSNBC.

“If you’re making a requirement for vaccination for people to get on planes who are coming into the country, that’s understandable. You don’t want to bring more cases into the country,” he said.

“But if you’re talking about requiring vaccination to get on a plane domestically, that is just another one of the requirements that I think is reasonable to consider,” added Fauci, who is director for the National Institute of Allergy and Infectious Diseases.

‘Another incentive’

Dr. Anthony Fauci appeared on MSNBC on Monday morning.

Fauci did not say whether he had made this recommendation to President Biden but added that a vaccination requirement for air travel creates more incentive to get vaccinated in the first place.

“You know, there’s requirements that you might want to get if you want to get into college, where you want to go to a university or you want to work in certain places,” he said.

“When you make vaccination a requirement, that’s another incentive to get more people vaccinated. If you want to do that with domestic flights, I think that’s something that seriously should be considered,” he said.

Biden said in an interview with ABC News that while vaccine requirements for domestic air travel were considered, “the recommendation I’ve gotten is not necessary.”

Current travel requirements

For domestic air travel, the US Centers for Disease Control and Prevention recommends you delay air travel until you’re fully vaccinated. If you’re not fully vaccinated, the CDC suggests you get tested one to three days before your trip and get tested three to five days after returning.

What is required: Travelers must wear a face mask over the nose and mouth on planes, buses, trains and other forms of public transportation. They must also wear them indoors at transportation hubs such as airports and train stations.

Travelers do not have to wear a mask in areas exposed to the outdoors such as the open deck areas of a ferry or the uncovered top deck of a bus.

Read more about the domestic rules and recommendations from the CDC here.

For international travel, all air passengers ages 2 or older must show a negative result of a Covid-19 test or documentation of recovery from Covid-19 before boarding a flight to the United States. This rules applies to everyone – regardless of citizenship or vaccination status. The test must be taken within one day of departure for the United States.

And people who are not US citizens, US nationals, lawful permanent residents or traveling to the United States on an immigrant visa need to show proof of being fully vaccinated before travel by air from a foreign country.

Read more about the international rules and recommendations from the CDC here.

Top image: Travelers pass through Salt Lake City International Airport on Friday, December 24. (Rick Bowmer/AP).

CNN’s Forrest Brown contributed to this article.