WASHINGTON (Reuters) -The chief executives of low-cost carriers Allegiant Airlines and Frontier Airlines will testify before a U.S. Senate Judiciary antitrust subcommittee on Tuesday on air carrier competition, congressional aides said.

Allegiant Airlines CEO Greg Anderson and Frontier Airlines CEO Barry Biffle are among the witnesses that will testify, as will Sharon Pinkerton, a senior vice president at Airlines for America, which represents United Airlines, Delta Air Lines ( DAL ), American Airlines ( AAL ), Southwest Airlines ( LUV ) and others.