Studio 'did not cave over film'
The head of Sony Pictures has insisted the studio has "not caved" over the decision to cancel the release of a movie about a plot to assassinate North Korean leader Kim Jong Un.
At his end-of-year press conference, US president Barack Obama said Sony had "made a mistake".
Online hackers made terrorist threats against cinemas that chose to screen controversial film The Interview.
North Korea has proposed a joint investigation with the US to find the perpetrators of the attack that saw thousands of internal Sony files leaked online.
Mr Obama criticised Sony's decision to cancel the release.
He said : "I wish they had spoken to me first.
"We cannot have a society in which some dictatorship some place can start imposing censorship."
But Michael Lynton, the company's chief executive, said Mr Obama himself was "mistaken" in his criticism.
Mr Lynton told US network CNN that the release was only scrapped after all major cinema chains decided not to show the film.
He said: "The president, the press and the public are mistaken as to what actually happened. We do not own movie theatres. We cannot determine whether or not a movie will be played in movie theatres.
"We have not caved, we have not given in, we have persevered and we have not backed down."
An unidentified foreign ministry spokesman in Pyongyang claimed the US would face unspecified "grave consequences" if proposals for a joint investigation were rejected, and said the North Korean government knew how to prove it was not responsible for the hacking.
But the FBI has insisted the online attack was carried out by North Korea.
Sony has suggested that it could now release the movie on DVD or through video-on-demand services.
The company said: "The only decision that we have made with respect to release of the film was not to release it on Christmas Day in theatres, after the theatre owners declined to show it.
"After that decision, we immediately began actively surveying alternatives to enable us to release the movie on a different platform."
Hollywood star George Clooney said the entertainment industry should push for immediate release of The Interview online.
He told the trade site Deadline that Sony should "do whatever you can to get this movie out".
"Not because everybody has to see the movie, but because I'm not going to be told we can't see the movie," he added. "That's the most important part".
Foreign Secretary Philip Hammond said he was "deeply concerned" at the US agency's findings.
Since the attack on Sony's internal network, which was carried out by a group calling itself The Guardians of Peace, thousands of emails, personal details and even films from Sony have been leaked online.
As well as the cancellation of The Interview, a film which North Korea called an "act of war", the cyber attack has seen emails between Sony executives criticising Angelina Jolie and the personal details and social security numbers of thousands of staff appear online.
The Guardians of Peace has since praised Sony's decision to cancel The Interview's release, and told CNN that no more Sony data would be released if the firm continued to comply.