Delta Air Lines said it will delay the launch of its nonstop service between Atlanta and the Saudi capital Riyadh until March after several deadly attacks hit the city's airport there.

Delta planned to begin the route on Oct. 23, with an Airbus A350-900 wide-body plane, in what would have marked the first nonstop commercial flight between the U.S. and Saudi Arabia operated by a U.S. airline.

Since Thursday, more than 2,000 flights have been canceled to and from King Khalid International Airport in Riyadh, according to FlightAware. The deadly attacks, claimed by Yemen's Iran-backed Houthis, escalated Saturday, when a projectile struck a passenger terminal at the airport, officials said, killing at least 12 people and wounding more than 300.

King Khalid International Airport remains closed as of Monday.

"We remain in close contact with relevant government and aviation partners, including Saudia and Riyadh Air, as we monitor the situation," Delta said in a statement. "Saudi Arabia remains an important market for Delta, and we are committed to serving the Kingdom for the long-term."

Delta CEO Ed Bastian had told CNBC on Thursday that the airline hadn't yet decided whether to postpone the debut.

"Obviously, we were disappointed to see the news this week," he said. "Safety is going to make the call."

Delta's decision came after the Federal Aviation Administration on Sunday issued a warning for U.S. airlines.

The FAA said pilots should "exercise caution" in or around Saudi Arabia "due to safety-of-flight risks associated with ongoing military activities" and navigation systems. In the warning, which is in effect until Dec. 10, the agency said the threats could be a potential risk "to aircraft at all altitudes."

Airlines suspended flights to the airport, some for the rest of the week, while countries including the U.S. and Australia advised citizens against travel to the region.

— CNBC's Michele Luhn contributed to this report.