North Korea has denied orchestrating a cyber-attack on Sony Pictures in retaliation for an upcoming Hollywood movie that depicts an assassination plot against leader Kim Jong Un.

North Korea has denied orchestrating a cyber-attack on Sony Pictures in retaliation for an upcoming Hollywood movie that depicts an assassination plot against leader Kim Jong Un.

But an unidentified spokesman for the North's powerful National Defence Commission clearly relished the blow to the Culver City, California, company that he said was producing a film that was "abetting a terrorist act" and "hurting the dignity of the supreme leadership" of North Korea.

The spokesman said today the attack "might be a righteous deed of the supporters and sympathisers" of the North, and South Korea "groundlessly linked the hacking attack with" Pyongyang.

Last week's cyber-attack disrupted Sony Pictures' computer system and spewed confidential information on to the internet.

The film, The Interview, is a comedy starring Seth Rogen and James Franco.

"We do not know where in America the Sony Pictures is situated and for what wrongdoings it became the target of the attack, nor (do) we feel the need to know about it," the statement carried in state media said.

"But what we clearly know is that the Sony Pictures is the very one which was going to produce a film abetting a terrorist act while hurting the dignity of the supreme leadership of" North Korea.

North Korea has built a cult personality around the Kim family, which has ruled for three generations, and sees any outside criticism of mockery of its leader as an attack on its sovereignty. It recently opened fire on anti-Pyongyang propaganda balloons that North Korean defectors in the South were floating across the border into the North.

The Interview's plot concerns an attempt on the life of Kim and Pyongyang is not amused.

The North's denial also included a threat.

The United States should know that "there are a great number of supporters and sympathisers with (North Korea) all over the world as well as the 'champions of peace' who attacked the Sony Pictures," the statement said.

"The righteous reaction will get stronger to smash the evil doings."

Some cyber-security experts say they have found striking similarities between the code used in the hack of Sony Pictures and attacks blamed on North Korea that targeted South Korean companies and government agencies last year.

Experts are divided, however, over the likelihood that North Korea or independent hackers were involved.

ends