US Senator Charles Schumer wants to require the Federal Aviation Administration to establish seat-size standards for commercial airlines, which he says now force passengers to sit on planes "like sardines".
The New York Democrat told The Associated Press that airlines have been slowly cutting down leg room and seat width.
"One of the most vexing things when you travel on an aeroplane is there's almost no leg room on your standard flight," Schumer said.
"There's been constant shrinkage by the airlines."
He said he will add an amendment to the FAA Reauthorization Bill that is pending before Congress that would require the agency to set the seat-size guidelines.
Schumer planned to formally announce the proposal at a news conference on Sunday.
Schumer said the average distance between rows of seats has dropped from 89cm in the 1970s to a current average of about 79cm. He argues that the requirement is needed to stop airlines from shrinking seats and seat pitch, the distance between rows of seats on aeroplanes, even further.
"They're like sardines," Schumer said of aeroplane passengers.
"It's no secret that airlines are looking for more ways to cut costs, but they shouldn't be cutting inches of leg room and seat width in the process ... It's time for the FAA to step up and stop this deep-seated problem from continuing."
Currently, there are no federal limits on how close an airline's row of seats can be or how wide an airline's seat must be.
Congress typically renews the FAA's authorisation every four to six years, using the bill as an opportunity to address a wide range of aviation issues. A vote is expected in March.
Airlines for America, an industry trade group, said the government's role was to determine a safe seat size, but opposed the proposed regulation.
"We believe the government should not regulate, but instead market forces, which reflect consumer decisions and competition should determine what is offered," spokeswoman Jean Medina said.
"As with any commercial product or service, customers vote every day with their wallet."
