Qantas and Japan Airlines will pour an additional $114m into Jetstar Japan as the franchise prepares to launch international flights early next year.
The top-up will be evenly split between Qantas and JAL and see their stakes in Jetstar Japan increase to 47.1% each.
From its launch in mid-2012 the airline holds an estimated 60% share of Japan's burgeoning low-cost market and is now looking to grow beyond its domestic network.
By year's end the Jetstar Japan fleet will number 20 single-aisle Airbus A320 aircraft, with bases at Tokyo/Narita and Osaka's Kansai Airport.
Kansai has proven especially useful to Jetstar Japan for its curfew-free status, which the airline says has lead to "an increase of flying by 20%."
Jetstar Japan is one of several Asian offshoots of the low-cost Jetstar brand, which includes the regional anchor Jetstar Asia and still-to-fly Jetstar Hong Kong.
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