TOKYO: Japan is to launch a new spy satellite on Sunday to strengthen its monitoring capabilities amid concern that North Korea may carry out more missile and nuclear tests.

A rocket carrying a radar-equipped satellite is scheduled to blast off from a space centre at Tanegashima in the southwest, the Japan Aerospace Exploration Agency has announced.

The space agency said the satellite would be used for information-gathering, including data following Japan's 2011 quake and tsunami, but did not mention North Korea by name.

The launch, planned for Sunday between 1:00 and 3:00 pm (0400-0600 GMT) comes after Pyongyang rejected dialogue on its atomic programme following tightened UN sanctions for a banned rocket launch.

The North's foreign ministry responded angrily to the UN Security Council action, saying there would be "no dialogue to discuss denuclearisation" and hinting that a new atomic test could be planned.

Japan hopes the satellite launch will enable it to complete a system first devised in the early 1990s as a response to fears about North Korea.

From an altitude of several hundred kilometres, the satellite will be able to detect objects on the ground as small as a square metre, including at night and through cloud cover, thanks to its radar.

Tokyo has four operational satellites in space, of which just one is equipped with radar. It has used satellites for monitoring and information-gathering since the late 1990s.

Last year Pyongyang launched two long-range rockets. The first failed but the second in December flew over the southern Okinawa island chain, jangling nerves in Japan.

North Korea insists its December 12 rocket launch was a peaceful, scientific mission aimed at putting a satellite in space. The UN condemned it as a disguised ballistic missile test.