The government hailed the appointment of South Korea's Ban Ki-Moon as the new UN secretary general but said he faced "daunting" challenges following North Korea's declared nuclear test. He replaces Kofi Annan in January.

"There are some very daunting issues confronting the new secretary general and we hope that with his vast experience that he will be up to the task," Deputy Prime Minister Najib Razak told reporters.

"We hope that with his role as the secretary general of the United Nations, he will ensure the peace and security of the entire Asian region," he added.

Najib said Malaysia hoped Ban, a career diplomat and the current South Korean foreign minister, would understand the aspirations of Asia, which is the fastest-growing region in the world.

"And at the same time (he should) be able to handle the problems of the Middle East and some of the challenges obviously relating to North Korea's wish to become a nuclear power," he said.

Najib said Malaysia would give Ban its "fullest cooperation to ensure the UN becomes an effective world institution."

Ban is the second Asian after U-Thant of Burma to hold the position and the eighth secretary-general in the UN's 60-year history.