The director of the Pyongyang Friendship Hospital, which treated American student Otto Warmbier, who died last year after being detained for months in the country, has dismissed new allegations that his death resulted from torture.

The North's official Korean Central News Agency on Saturday quoted the unnamed hospital director as saying the claims were a "total distortion of the truth," and that the 22-year-old Warmbier, who was repatriated to the United States in a coma after months of silence about his fate following a show trial in Pyongyang in March 2016, had been treated humanely.

"The American doctors who came to the DPRK to help Warmbier's repatriation acknowledged that his health indicators were all normal and submitted a letter of assurance to our hospital that they shared the diagnostic result of the doctors of our hospital. That document is still in our hands," the hospital director was quoted as saying.