North Korean leader Kim Jong-un's threats to take "merciless countermeasures" against the U.S. if Seth Rogen's new comedy The Interview is released as planned on Christmas Day (25Dec14) have left the funnyman's mother terrified.

The actor/producer's new film centres upon two hapless U.S. journalists who are recruited to kill the North Korean dictator after landing an opportunity to interview him. Rogen and pal James Franco play the Tv presenter and his sidekick.

As soon as the trailer was released earlier this year (14), Kim Jong-un's aides declared the film a "most wanton act of terrorism and war" and threatened to strike back if Sony bosses went ahead with plans to release the movie.

Rogen tells Rolling Stone magazine he's still stunned that his comedy has sparked a major international incident - and admits his mum is worried for his safety.

He explains, "For a Jewish mother, having a country wage war on your son is the worst. No Jewish mother should have to deal with that.

"If Kim Jong-un only knew what he was doing to my mother! He would know he had exacted his revenge."

Activists calling themselves the Guardians of Peace have threatened to continue hacking into Sony's computers and releasing stolen files featuring celebrities' salaries and personal information and whole movies unless studio bosses scrap plans to release the film.