North Korea has threatened to use nuclear weapons if provoked by South Korea and the US.

North Korea has said it is planning for a retaliatory war against the US and South Korea in response to military exercises by those countries.

This weekend the US and South Korea are launching a large-scale joint naval exercise off the coast of the peninsula in what they say is a show of deterrence against any further acts of aggression.

North's Korea's National Defence Commission said it was prepared to use nuclear deterrents in the face of ‘provocation’.

‘All these war manoeuvres are nothing but outright provocations aimed to stifle the DPRK (Democratic People's Republic of Korea) by force of arms to all intents and purposes,’ the powerful commission said in a statement carried by North Korea’s official KCNA news agency.

The US said it had no interest in getting into a 'war of words' with North Korea.

Tensions between North and South Korea have been high since the sinking of a South Korean warship in March.

North Korea has again denied it was behind the sinking of the 'Cheonan' and said the planned military drills were ‘as reckless an act as waking up a sleeping tiger’.

North Korea has called for the resumption of six-party nuclear disarmament talks that it had boycotted since late 2008, a move analysts said was an attempt to put the warship incident behind and win lucrative aid through a deal with the South, the US, Japan, Russia and China.

The US and South Korea have rejected the call and said Pyongyang must first prove that it is genuinely interested in change by first apologising for sinking the 'Cheonan'.

Following talks in the South Korean capital of Seoul on Wednesday, US Secretary of State Hillary Clinton announced fresh sanctions on North Korea aimed at freezing its assets earned from illicit activities including arms trade and cut off the flow of cash to its leaders.