Sony Pictures says it still hopes to release its controversial film about a plot to assassinate North Korean leader Kim Jong Un.
The comedy, "The Interview," was the trigger for a massive computer attack on the Hollywood company, which U.S. authorities blamed on North Korea.
North Korea denied it was responsible for hacking into Sony Pictures' computer network and posting embarrassing emails, other private data and unreleased film projects on the Internet. However, the communist state praised the computer attack as "a righteous deed."
Pyongyang said it could prove it was not involved, and it proposed Saturday to carry out a joint investigation of the hacking with the United States.
In an odd footnote, an unidentified spokesman for the North Korean Foreign Ministry then warned of "grave consequences" if Washington failed to accept the invitation to join an investigation.
In Washington on Saturday, a spokesman for the White House National Security Council, Mark Stroh, said the U.S. stood by its assertion that North Korea was behind the cyberattack.
He said, "The government of North Korea has a long history of denying responsibility for destructive and provocative actions.'' He said if Pyongyang wanted to help, it could admit its culpability and compensate Sony for the damages the attack caused.
In another development Saturday, the chairman of the Republican National Committee, Reince Priebus, encouraged the chief executive officers of 10 major cinema chains to show the movie. Priebus said he wanted it to be screened "to show North Korea we cannot be bullied into giving up our freedom."
Sony canceled the scheduled December 25 release of the satirical comedy at the center of the incident Wednesday.
The hackers who penetrated the film company's computer network and stole thousands of documents call themselves "the Guardians of Peace." They warned there would be a "bitter fate" for anyone attending a public showing of the movie.
Sony Pictures Chairman Michael Lynton told reporters Friday that the studio had no choice but to cancel the film's release, because American theaters were unwilling to show it. However, he told interviewers that Sony did not "give in" or "cave" (surrender) to the hackers, and that it was trying to find some format for showing the film, possibly through a video-on-demand service or over the Internet.
Speaking Friday at the White House, President Barack Obama said Sony made a mistake in canceling the film release.
The president said, "We cannot have a society in which some dictator someplace can start imposing censorship here."
Obama said he was "sympathetic" that Sony, as a private company, was worried about the risks it faced, but he added: "I wish they would have spoken to me ... [and not be] intimidated by these types of criminal attacks."