U.S. airline passengers who refuse to wear face coverings during the novel coronavirus pandemic could have their flying privileges revoked under tougher enforcement policies, the industry's main lobby group said Monday.

Major U.S. airlines may prevent anyone not wearing a mask from boarding and provide the coverings to passengers who have none. Once on board, however, flight attendants have had little power over passengers who remove the face covering.

Carriers with the stricter policy include Alaska Airlines , American Airlines, Delta Air Lines, Hawaiian Airlines, JetBlue Airways, Southwest Airlines and United Airlines, Airlines for America said in a statement.