WASHINGTON — A government proposal that would force air travelers to pay up to $200 a year for a fast pass through airport security could kill the program, advocates and lawmakers said Wednesday.

That price — double what was expected — would "severely threaten" the long-delayed Registered Traveler program, said Steven Brill, a Manhattan entrepreneur planning to launch the idea at four airports this year.

Eagerly awaited by travelers and recently touted by Homeland Security Secretary Michael Chertoff, Registered Traveler offers fee-paying fliers expedited airport screening. Travelers in the program would have to pass a background check to rule out ties to terrorism and would get an ID card to speed them through checkpoints.

The Transportation Security Administration said last year that it expected to charge about $30 for a terrorism check. Now it wants to charge another $70 to pay for TSA screeners at Registered Traveler checkpoints, TSA spokeswoman Ellen Howe said. It also may charge an additional $20 for a criminal background check. Those costs are in addition to yearly fees of up to $80 that fliers would pay to companies operating the program.

[Rep. Bennie] Thompson, the congressman, said a $200 fee might deter travelers who already get shorter security lines through elite flier clubs.

Frequent travelers had mixed views.

Cleveland businessman Mark Taft said $200 is "on the outer edge of what I would pay."

Charlie Massoglia said paying $200 "doesn't make a difference to anyone who travels frequently."