WELLINGTON, New Zealand (AP) - Australia's largest airline Qantas Airways plans to expand flights within New Zealand in a significant shakeup of the market.

WELLINGTON, New Zealand (AP) Australia's largest airline Qantas Airways plans to expand flights within New Zealand in a significant shakeup of the market.

Qantas subsidiary Jetstar said Thursday it planned to add at least four new destinations starting December to the five cities in New Zealand it already serves. That will increase its competition with Air New Zealand, which currently enjoys a monopoly on many routes.

Air New Zealand shares fell 9.4 percent Thursday in response to the announcement.

Jetstar started flying New Zealand routes a decade ago and, by its own estimation, has a 21 percent share of the market based on kilometers flown or a 17 percent share based on passenger numbers.

Jetstar currently flies to Auckland, Wellington, Christchurch, Dunedin and Queenstown. It has yet to announce the planned new destinations.