United Airlines is drastically reducing operations at two New York-area airports amid the coronavirus pandemic.

The temporary reductions at Newark Liberty International Airport and LaGuardia Airport take effect Sunday and will last at least three weeks, according to a letter to United employees obtained by USA TODAY.

New York City has been hit especially hard as COVID-19 spreads, with more than 63,300 confirmed cases and 1,905 deaths as of Saturday evening, according to the Johns Hopkins University Coronavirus Resource Center.

Nationwide, there are currently more than 308,530 confirmed COVID-19 cases and 8,376 deaths.

At Newark, one of United's hubs, the carrier will drop from its current 139 flights per day to 62 destinations to 15 daily flights to just nine destinations.

At LaGuardia, United will go from 18 flights per day to four destinations to two daily flights to one destination.

To provide a bit of context, more than 550 flights took off from LaGuardia, John F. Kennedy and Newark airports last Sunday alone, according to flight tracker FlightAware.

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"As the situation in New York and New Jersey worsens, we are taking another major step at Newark and LaGuardia to help keep our employees safe and play our part in helping to mitigate the spread of the outbreak in the Tri-State area," Greg Hart, United's executive vice president and chief operations officer, said in the letter to employees.

Why are airlines flying to hot spots like New York at all? The federal government underscored its position with a key provision in the $2 trillion coronavirus aid package approved last week: airlines that accept a share of the $50 billion set aside for the industry must maintain a minimum level of service through at least September.

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Hart stressed that United employees affected by the reduction in operations will continue to be paid.

"Importantly, whether you are on duty or not, we will maintain the pay and benefits of *all* local employees scheduled to work in those locations during this temporary reduction," he wrote. "And we will be flexible in accommodating any employees who commute to either of these stations and ask our ground-based employees to remain on call for critical and immediate operational needs as they arise, like diversions and humanitarian flights."

As COVID-19 continues to spread across the U.S., Hart said United could potentially make similar moves at airports in future hotspots.

United, like all carriers, has slashed flights in recent weeks as business and leisure travel has dried up due to coronavirus fears.

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Meanwhile, the carrier said Friday that it is offering free flights to medical volunteers heading to New York to treat patients diagnosed with the coronavirus.

In a press release, United said it is working with the Mayor's Fund to Advance New York City and medical volunteer organizations to coordinate the travel for doctors and nurses, as well as arrangements for housing and transportation once they arrive.

"Our healthcare workers are heroes, and they need reinforcements," New York Mayor Bill de Blasio said in the press release. "This generous partnership with United Airlines will ensure medical professionals from across the country can come to New York City to help us in our hour of need."

The program will likely spread to other cities in the coming weeks, United said.

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Contributing: Dawn Gilbertson, Bart Jansen, USA TODAY