Pyongyang, Apr 2 (IANS): North Korea Tuesday said it has decided to restart operations at the Nyongbyon nuclear complex.

A spokesman for the General Department of Atomic Energy told the official KCNA news agency that the country will "readjust" and "restart" all nuclear facilities at the complex, including a uranium enrichment plant and a 5MW graphite moderated reactor that had been "mothballed and disabled under an agreement reached at the six-party talks in October 2007".

The spokesman said the decision was made at a plenary meeting of the Central Committee of the ruling Workers' Party of Korea March 31 to cure the country's electricity shortage and boost up nuclear armed forces, reported Xinhua.

Such a move came days after North Korea claimed that it had entered a "state of war" with South Korea.

South Korean President Park Geun-hye Monday instructed the military to strongly respond to possible provocation by North Korea without any political considerations.

Tensions have been running high on the Korean Peninsula since North Korea conducted its third nuclear test Feb 12 as a countermeasure against the joint military drills of the US and South Korea.

North Korea has also threatened to launch a pre-emptive nuclear strike for self-defence and unilaterally nullified the 1953 armistice that suspended the Korean War.

The US Navy was moving a sea-based radar platform closer to the Korean Peninsula in order to monitor military moves of North Korea, including possible new missile launches, CNN quoted a Pentagon official as saying Monday.