Southwest Airlines announced on Tuesday that it would slash over 40 percent of flights starting May 3 to June 5 as a result of a sharp drop in demand caused by an ongoing global virus problem.

The Dallas-headquartered carrier said it would operate 2,000 flights per day over standard rates, down 1,700. The carrier said that for the current month, it would be canceling 1,500 flights a day.

Southwest disclosed it would retain more than 80 percent of the routes it had previously provided, but added that certain non-stop flights would now need a connecting flight. The company is also cutting its day of service, reducing several regularly scheduled departures before 7 am and after 8 pm.

According to chief commercial officer Andrew Watterson, the carrier has worked earlier to announce improvements by revising its simple flight schedule from mid-April through early May. "The move gives us more time for improvements and enables our network operations to concentrate on daily operations."

Southwest Airlines is parking more aircraft and exploring employee early retirement incentives as the carrier seeks to further slash costs to account for a dramatic decrease in passengers caused by the coronavirus crisis, chief executive officer Gary Kelly said on Monday.

Kelly said the organization has to concentrate on "conserving cash and making sound financial choices" in a video message to workers to help manage the unexpected economic challenges arising from the downturn caused by the pandemic and global efforts to curb its spread.

Southwest will start adding some flights back outside the continental United States in late May by resuming flights from Houston Hobby to Cancun, Baltimore to Jamaica, and Los Cabos and bringing back flights from Oakland to Hawaii. It cut a huge volume of its Hawaii operations after the state issued a 14-day quarantine order for people arriving in the islands.

Southwest has a workforce of about 62,000, including 10,000 in Dallas. But since the United States became the top country with the most number of Covid-19 infections, restrictions on travel and social gathering have become more severe, including a 14-day ban for those traveling from states including New York, California, Washington and Louisiana to Texas.

On Sunday, according to data from the Transportation Security Agency, the number of passengers arriving at airports fell by more than 92 per cent compared to a year earlier.

As of Monday, 50 of Southwest Airlines' 737-700 planes have been parked in Victorville, California. That's up from the 24 it announced two weeks ago and more than a year after the Federal Aviation Administration grounded the aircraft, in addition to the 34 Boeing 737 Max jets in storage.