China Southwest Airlines is assessing the Airbus A319 and Boeing 737-700 for its first intra-Tibet services.
Airbus carried out local demonstration flights late last month between the 14,200ft- (4,330m) high Bangda Airport in eastern Tibet - the world's highest airport - and the 11,700ft-high Gonggar airport near Lhasa.
Boeing carried out similar demonstration flights for the carrier last September at the airports.
China Southwest operates Boeing 757s and Airbus A340s to Tibet from points in China, but there are no flights within the Chinese-controlled territory.
The carrier has not indicated when a decision is to be taken on new narrowbody leases or purchases. The 737-700 has an advantage as China Southwest, which is to be taken over by Air China, already operates 737-800s and has committed to leasing smaller 737-600s.
Source: Flight International