More than 500 pilots and flight attendants with financially troubled Mexicana de Aviacion demonstrated inside Mexico City's airport to protest possible layoffs or salary reductions.
Pilots and attendants chanting "Inept businessmen, enough!" on Sunday marched by Mexicana's counter holding banners that read "Pilots in defense of jobs and passenger safety."
Pilots' union president Fernando Perfecto said they sent a letter to President Felipe Calderon asking him to intervene in their contract negotiations with Mexicana.
"Employment, Mr President, a topic that you enshrined as the cornerstone of your administration, is being seriously harmed by the grave financial and corporate deterioration of Mexicana de Aviacion," the letter said.
The company is suggesting layoffs, salary reductions and less training as part of a new workers contract that is looking to slash expenses, Perfecto said. He said air carrier executives have told the union the airline could file for bankruptcy in the coming weeks.
Flight attendant union President Lizzeth Clavel said Mexicana is proposing to lay off 500 attendants.
"The company has been converted into a nonviable product and its directors will have to answer to society and to justice for that," Perfecto said.
No one answered calls at Mexicana's headquarters seeking comment on Sunday but company executives have said the air carrier is going through a critical financial situation and that it is analyzing ways to keep operating.
Perfecto and Clavel said Mexicana gave the unions until Aug 9 to reach a new labour agreement.