Washington: In rare free moments, when Kim Jong-un isn't calling US President Donald Trump a dotard, launching ballistic missiles into the Sea of Japan or engaging in general dictatoring, he apparently goes on leisurely mountain hikes and flexes his never-before-reported superpower: controlling the weather.

The case for the North Korean leader's cameo role in a new X-Men movie came during a brisk three-kilometre stroll up snowy Mount Paektu a week or so ago, as reported by the state-controlled Korean Central News Agency.

The 2744-metre mountain is normally a wintry mess in December, according to the news agency, but during Kim's visit, it was a "marvellous scene with glee at the reappearance of its great master." When Kim ascended to the top, the mountain showed "fine weather unprecedented".

It was obviously an homage to Kim, KCNA reported, the man "who controls the nature".