WASHINGTON, July 19 — Federal aviation authorities have decided to stop enforcing a two-year-old rule against taking cigarette lighters on airplanes, concluding that it was a waste of time to search for them before passengers boarded.

The ban was imposed at the insistence of Congress after a passenger, Richard Reid, tried to ignite a bomb in his shoe in 2001 on a flight from Paris to Miami.

Lawmakers said that if Mr. Reid had used a lighter, instead of matches, he might have been able to ignite the bomb, but Kip Hawley, assistant secretary for the Transportation Security Administration, said in an interview on Thursday that the ban had done little to improve aviation security because small batteries could be used to set off a bomb.

Matches have never been prohibited on flights.

“Taking lighters away is security theater,” Mr. Hawley said. “It trivializes the security process.”