North Korea has written a letter to Australia to complain about the “heinous and reckless moves” of Donald Trump and to warn of the global nuclear disaster that could result from any attempt to topple the regime in Pyongyang.

Dismissing the unusual letter as "basically a rant", Australian prime minister Malcolm Turnbull said it was North Korea that had upped the nuclear threat level.

"It is North Korea that is threatening the stability of the world,” he told 3AW radio.

"That is the regime that has to return to its senses and stop this reckless conduct."

Mr Turnbull said the letter was also sent to other countries, though no others have yet been named.