A spokesman for Pyongyang's foreign ministry said Friday the U.S. senator is "human dirt" and a "psychopath" for his unflattering characterization of the North Korean leadership.
"On May 3, some [expletive] by the name of Cory Gardner, who sits on the U.S. Senate Foreign Relations Committee, perpetrated wicked blasphemy against our supreme dignity during an interview with NBC," the statement on KCNA read.
"For a psychopath like the [expletive] Gardner, to hurl evil accusations at our highest dignity, is a serious provocation," the Pyongyang spokesman said. "That a man mixed in with human dirt like Gardner, who has lost basic judgment and body hair, could only spell misfortune for the United States."
On Wednesday, Gardner slammed Kim during an interview on MSNBC's Morning Joe.
"I think most people agree that Kim Jong Un is a whack job," Gardner said. "This is a crazed maniac at the helm of one of the world's nuclear regimes, trying to become a nuclear regime.
"We shouldn't be in the position of flattery."
Tensions have grown between Washington and Pyongyang as North Korea continues tests of ballistic missiles and the United States sends strategic military assets to the peninsula.
On Thursday, the passage of a new sanctions bill aiming to block all funds that support the North Korean regime was met with criticism from China.
Beijing's foreign ministry spokesman Geng Shuang said Friday the "situation on the Korean peninsula is highly complex" while referring to the U.S. bill, South Korean news agency Yonhap reported.
The ministry said actions should not "worsen tensions on the peninsula."