SYDNEY, Dec 18 (Reuters) - Australia will carry out both airframe and engine maintenance for South Korea's fleet of Lockheed Martin Corp F-35 fighter jets, as well as its own fleet, an Australian defence source told Reuters on Thursday.

The Pentagon said on Wednesday it chose both Japan and Australia to carry out heavy airframe maintenance for the stealth fighters in Asia, given the high cost of transporting jets across vast distances in the region.

(Reporting by Matt Siegel; Additional reporting by Lincoln Feast; Editing by Paul Tait)