Labelling the launch a ''provocative and irresponsible act, Prime Minister Julia Gillard and Foreign Minister Bob Carr issued a statement unequivocally condemning the action, which they said threatened the stability of the region.

''North Korea's testing of long-range rockets violates United Nations Security Council resolutions and the Security Council's Statement earlier this year, and it defies the will of the international community,'' the pair said.

''Australia urges the Security Council to meet urgently and respond firmly.''

They said North Korea's people struggled to feed themselves, while their government threw money at its second costly long-range rocket launch this year.

''We call on the North Korean Government to abide by UN Security Council resolutions, stop its provocations, improve the wellbeing of its people, and engage constructively with the international community.

''Australia will be expressing its concerns directly to the North Korean Government.''

The Yonhap news agency, citing a government source, said the rocket had been launched from the Sohae satellite launch centre at 9.51am (11.51 AEDT).

The launch followed reports in the South Korean media and satellite imagery analysis by US experts that suggested the rocket had been removed from the launch pad to repair an apparent technical problem.

North Korea had originally provided a December 10-22 launch window, but extended that by a week on Monday when a ''technical deficiency'' was discovered in the first-stage control engine.

North Korea last attempted to launch its three-stage Unha-3 carrier in April, but the rocket exploded shortly after take-off.

with AAP