North Korea said Sunday it had successfully placed a satellite in orbit in an "epochal event" to boost its defence capability, with a rocket launch widely condemned as a ballistic missile test.

A state television announcer said the launch, personally ordered by leader Kim Jong-Un, had "successfully put our Earth observation satellite Kwangmyongsong 4 ... into orbit."

The satellite, launched at the Sohae launch base in the country's northwest at 9:00am Pyongyang time (0030 GMT), entered orbit about 10 minutes later.

The formal statement was read by Ri Chun-Hee, a star presenter known for her bombastic style of announcing major events including last month's shock nuclear test.

"The complete success made in the Kwangmyongsong-4 lift-off is ... an epochal event in developing the country's science, technology, economy and defence capability by legitimately exercising the right to use space for independent and peaceful purposes," Ri said.

The North would continue to push forward its space programme, she said, adding the latest satellite, carrying various measuring and telecommunication devices, was circling the polar orbit at a cycle of 94 minutes and 24 seconds.

"The National Aerospace Development Administration of the DPRK will, in the future, launch more satellites ... true to the great Workers' Party of Korea's policy of attaching importance to science and technology," she said.

The launch drew immediate criticism from Seoul and its ally Washington, with South Korean President Park Geun-Hye urging a "strong" UN Security Council response to what she described an "unacceptable provocation."