Delta, United and American on Friday announced they would halt service to mainland China as the rapid spread of coronavirus and government warnings against travel to the country drove down demand for flights there.

Large U.S. corporations, from Apple to Ford to Kraft Heinz, have restricted their employees' China business travel or scaled back operations because of the outbreak

United, which has the most service to China of the U.S. airlines, said starting Feb. 6 it would suspend flights from its hubs to Beijing, Shanghai and Chengdu until March 28. "Until that date, we will continue to operate select flights to help ensure our U.S. based employees, as well as customers, have options to return home." United said in a statement. The Chicago-based airline will continue to operate a once-daily San Francisco-Hong Kong flight. "As always, the safety of our customers and employees is our highest priority and we will continue to monitor the situation as it develops."

American said Friday it would immediately suspend its service to mainland China through March 27. American flies to China from Dallas/Fort Worth International Airport and Los Angeles International Airport, but the carrier will continue to fly to Hong Kong, a spokesman said.

Delta said it would halt China service starting Feb. 6 and through April 30, but it will continue to operate the service until then to "ensure customers looking to exit China have options to do so."

Earlier this week the airlines announced they would significantly cut back on China service but the escalation of the virus prompted them to suspend service. The State Department has advised against travel to China, and has permitted nonemergency employees at its diplomatic offices there to leave.

Stocks plunged Friday on concerns over the increasing impact of the coronavirus, with airlines down more sharply than the broader market. In early afternoon trading Delta was off 2.2%, United was down 3.4%. American shares were 3.3% lower.

The increasing isolation of China in the business world is echoed in the Trump administration's actions and rhetoric. The president himself has characterized the outbreak as largely a Chinese problem that is "under control" in the United States. Commerce Secretary Wilbur Ross, meanwhile, said this week that the coronavirus could actually be positive for American manufacturing and jobs as companies reevaluate their supply chains.

Some airline employees say it is easier if there is an outright ban on China travel from the U.S. government because it provides greater clarity and makes planning easier compared with frequently changing schedules according to new warnings.

Dozens of carriers around the world including United, Cathay Pacific, British Airways and others have slashed or suspended service to China because of the outbreak. Delta was the first in the U.S. to suspend service altogether. Large companies spanning industries from technology to packaged food have suspended business trips to the country because of coronavirus, driving down demand for flights to China.

— CNBC's Michael Calia and Phil LeBeau contributed to this report.