NORTH Korea has threatened "thousands-fold" revenge against the United States for banning exports worth $1billion following its intercontinental ballistic launches.

Crackpot leader Kim Jong-un is demanding "justice" over Donald Trump's attempts to "isolate and stifle" his country with ban on exporting coal, iron, lead and seafood.

The tough new U.N. sanctions could slash North Korea's $3 billion annual export revenue by a third.

State-controlled media carried a statement from the North that promised the move would never force the country to negotiate over its nuclear program – or to give up its nuclear drive.

It says it will take "action of justice" but didn't elaborate.

It's after US President Donald Trump and South Korean President Moon Jae-in agreed to apply maximum pressure and sanctions on North Korea in a telephone call on Monday.

The U.N. Security Council unanimously imposed new sanctions on North Korea on Saturday aimed at pressuring Pyongyang to end its nuclear programme.

The U.S.-drafted resolution bans North Korean exports of coal, iron, iron ore, lead, lead ore and seafood following Pyongyang's two intercontinental ballistic missile tests in July.