North Korea is adamant that it is not behind the Sony Pictures hacking, Fox News reported.

According to a press release on The Federal Bureau of Investigation's website earlier, it says that North Korea was responsible for the cyber attack.

"As a result of our investigation, and in close collaboration with other U.S. government departments and agencies, the FBI now has enough information to conclude that the North Korean government is responsible for these actions," the statement stated.

It added that according to " the tools used in the SPE attack have similarities to a cyber attack in March of last year against South Korean banks and media outlets, which was carried out by North Korea."

The attack is being blamed on the studio making the film 'The Interview' which plot revolves around the assassination of North Korea leader.

Although the release of the film, which was supposed to be this week, has been cancelled, the attack was so massive that news about information leaks has filled the Web.

New York Times meanwhile reported that North Korea has threatened to inflict "serious consequences" if the United States proceeds on retaliation against them.

President Obama on Friday meanwhile said that Sony should have went on and released the movie.

"We cannot have a society in which some dictators someplace can start imposing censorship here in the United States because if somebody is able to intimidate us out of releasing a satirical movie, imagine what they start doing once they see a documentary that they don't like or news reports that they don't like," Obama said. "That's not who we are. That's not what America is about."

Sony Pictures Entertainment CEO Michael Lynton in an interview with CNN's Fareed Zakaria was quoted as saying, "We have not caved, we have not given in, we have persevered, and we haven to backed down. We have always had the desire to have the American public see this movie."

Obama said the US will respond "proportionally" to North Korea. It did not say what would be the sanctions.