China will unveil its new generation J-20 stealth fighter jet at an air show next week, the air force said Friday, the first public showing of a warplane China hopes will narrow the military gap with the United States.

The ability to project air power is key for China as it takes on a more assertive stance on territorial disputes with neighbors in the East China and South China seas.

The Pentagon has said the fifth-generation stealth aircraft China is developing, the J-20 and the J-31, are necessary for China's air force to evolve from a mostly territorial force to one that can carry out both offensive and defensive operations.