North Korea upped its rhetoric on Sunday, accusing the US government of being "deeply involved" in the making of the movie The Interview and promising new attacks on "all the citadels of the U.S. imperialists," according to a statement reported on North Korea's state-run KCNA.

"The DPRK [Democratic People's Republic of Korea] has already launched the toughest counteraction," according to the statement, via CNN. "Nothing is more serious miscalculation than guessing that just a single movie production company is the target of this counteraction. Our target is all the citadels of the U.S. imperialists who earned the bitterest grudge of all Koreans. Our toughest counteraction will be boldly taken against the White House, the Pentagon and the whole U.S. mainland, the cesspool of terrorism."

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The statement also claims that "fighters for justice," including the "Guardians of Peace" -- a group responsive for the Sony cyberattack -- "are sharpening bayonets not only in the U.S. mainland but in all other parts of the world."

As for the movie, The Interview, the statement says: "The DPRK has clear evidence that the U.S. administration was deeply involved in the making of such dishonest reactionary movie." According to leaked emails, Sony consulted with members of the US State Department when making the satire, which depicts the assassination of North Korean dictator Kim Jong-un.

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There was no immediate reaction on the statement from the White House, which has termed the North Korean attack on Sony an instance of "cybervandalism."