North Korea is strongly denying U.S. accusations that Pyongyang is behind a cyberattack on Sony Pictures. The North’s foreign ministry described the U.S. accusations as “groundless slander” and said that it wanted a joint investigation into the incident with the United States.

The official KCNA news agency on Saturday quoted an unnamed spokesman of the North’s foreign ministry as saying there would be “grave consequences” if Washington refused to agree to the joint inquiry and continued to accuse Pyongyang.

On Friday, U.S. President Barack Obama vowed that the U.S. will respond  “proportionally” to the cyber attack on Sony Pictures the Federal Bureau of Investigation (FBI) has blamed on North Korea.

Speaking Friday during his annual end-of-year news conference at the White House, Obama said Sony “made a mistake” in canceling the release of a comedy about a fictional plot to assassinate North Korea’s leader Kim Jong Un as a result of the hackers’ threat to stage further attacks.   

Obama said he was sympathetic to Sony’s concerns, but added, “We cannot have a society in which some dictator someplace can start imposing censorship here.”  He also said there was no sign that North Korea worked together with another country on the cyber attack.   He said the U.S. will respond to the hacking in “a manner and time we will choose.” 
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