Philippine Airlines' cabin staff on Thursday formally advised the government they would go on strike at the end of October, saying the move would ground all flights by the loss-making flag carrier.
The 1,600-member cabin crew union said it had filed a strike notice with the labour ministry, which by law has 30 days to try to find a compromise between the airline and employees to prevent a shut-down.
"Once we go on strike, no flight will take off," said Bob Anduiza, president of the Flight Attendants Association of the Philippines.
"This will ground PAL's entire operations," he told a news conference.
PAL spokeswoman Cielo Villaluna appealed to the union to reconsider and return to the negotiating table.
"This will affect Philippine tourism and our financial position," Villaluna said in a radio interview.
The cabin staff are seeking a raise that would put their pay on par with that offered by foreign carriers. They are also demanding paid maternity leave and an end to a company policy that forces female attendants to retire at the age of 40.
There was no immediate comment from the labour department.
The planned strike is the latest in a string of labour problems to hit the national flag-carrier. Last month, 25 pilots and first officers of PAL's short-haul aircraft suddenly quit for higher paying jobs abroad, forcing the abrupt cancellation of several flights.