North Korea has described the UN's most recent set of sanctions against it as an "act of war".
On Friday, the UN Security Council agreed new sanctions, responding to missile tests carried out by North Korea.
Pyongyang has said the decision puts the stability of the Korean peninsula at risk, according to KCNA news agency.
The resolution agreed by the UN was drafted by the United States, which has been seeking to stop North Korea from building its nuclear capabilities.
The tough sanctions were supported by all of the members of the UN Security Council; one measure will cut North Korea's imports of petrol by as much as 90 per cent.
In a statement, North Korea said:
The United States, completely terrified at our accomplishment of the great historic cause of completing the state nuclear force, is getting more and more frenzied in the moves to impose the harshest-ever sanctions and pressure on our country.
The country plans to consolidate its nuclear defence, it said, with a view to eliminating the "nuclear threats, blackmail and hostile moves" of the US.
US President Donald Trump has been trading open insults with North Korean leader Kim Jong-un this year, saying he would "totally destroy" North Korea.
Jong-un hit back, saying the President is "mentally deranged".
Responding to the most recent sanctions, Trump said "The World wants Peace, not Death!"
The United Nations Security Council just voted 15-0 in favor of additional Sanctions on North Korea. The World wants Peace, not Death!— Donald J. Trump (@realDonaldTrump) December 22, 2017