SINGAPORE - All Jetstar Asia flights will have at least two people in the cockpit at all times, to deter malicious acts.
The new procedure will take effect from Wednesday, the airline said.
Jetstar's move follows discussions with the Civil Aviation Authority of Singapore (CAAS) in the wake of a crash in the French Alps on March 24.
A Germanwings co-pilot had locked his captain out and crashed the Airbus 320 aircraft with 150 people on board.
In its statement on Tuesday, Jetstar said that before one pilot needs to leave the cockpit for any reason, an operating crew member will enter and remain on the flight deck until the pilot returns.
"The safety and security of our customers and crew are our number one priority" the airline said.
Last Friday, the CAAS told The Straits Times that it had been discussing with all local carriers the implementation of the procedures aimed "to deter malicious acts".
A spokeman for Singapore Airlines' long-haul budget carrier, Scoot, said on Tuesday: "Scoot has put in place strict procedures regarding the security of our cockpits, but as company policy we will not be making public comments on matters relating to security."
CAAS has also stressed that there are procedures and systems in place to ensure pilots are equipped to do the job.
Before a professional pilot licence is given, a person must be certified medically fit through an assessment based on global standards.
Regular reviews are conducted every six months or once a year.
The medical assessments include a physical examination and psychiatric evaluation, the spokesman said.
Singapore carriers are required to have procedures to enable a pilot to report on a fellow pilot who, in the former's opinion, is not fit to fly.
They must also conduct security training programmes for all crew members to teach them how to deal with a colleague or passenger who could pose a risk.