U.S. President Donald Trump met on Wednesday with executives from some of the nation's top airlines who said they have stepped up procedures to keep planes "clean and disinfected" amid concerns about the coronavirus.

Executives from Southwest Airlines Co, United Airlines Holdings Inc, American Airlines Group Inc and JetBlue Airways Corp, among others, attended the meeting at the White House with Trump, Vice President Mike Pence and other top U.S. officials.

Trump said airlines would be affected by the fall in international travel related to the virus.

"It's affecting the airline business, as it would. And a lot of people are staying in our country and they're shopping and using our hotels in this country, so from that standpoint I think probably there's a positive impact, but there's also an impact on overseas travel which will be fairly substantial," Trump said.

He said the executives had not asked for financial assistance to make up for the hit to their businesses.

The airline executives said the industry was taking measures to intensify aircraft sanitation.

"We've stepped up our efforts to make sure the airplanes are clean and disinfected," said Southwest Airlines Chief Executive Gary Kelly.

"All of us have made a lot of changes to our cleaning procedures, changes to our onboard procedures, to gloves, sanitation," said Alaska Air Group Inc Chief Executive Brad Tilden.

United Airlines Chief Executive Oscar Munoz said his airline had promoted fist bumps as a way of greeting each other to reduce hand-to-hand contacts.

"We've invented the 'corona bump' at United, where you'll see us all bumping each other. It may sound silly, but it's a fun way of expressing what I think we all need to know, is be careful for the next few weeks as we control this; that we adapt our behavior so that indeed we can continue to stay safe."

American Airlines Chief Executive Doug Parker said American had offered flexibility to passengers who wanted to change their travel plans because of the outbreak.

"We put out a fare sale recently that allows customers the flexibility to book their travel in advance, and if they find they want to change that later, the change fees are waived," he said.