Updated

Australia's prime minister has dismissed an extraordinary letter from North Korea to the Australian Parliament and other countries as a "rant" against President Donald Trump and a sign that Pyongyang is "starting to feel the squeeze" of escalated sanctions.

The letter from the North Korean Foreign Affairs Committee attacks Trump over his speech to the United Nations General Assembly last month in which the president threatened to "totally destroy North Korea" if provoked.

Prime Minister Malcolm Turnbull told Melbourne Radio 3AW on Friday the letter was sent to "a lot of other countries" as well as Australia.

The letter says that if Trump thinks that he will bring North Korea "to its knees through nuclear war threat, it will be a big miscalculation and an expression of ignorance."