North Korea has rejected new sanctions by the United Nations Security Council, warning that the "forthcoming measures" will "make the US suffer the greatest pain" it has ever experienced.

Pyongyang's ambassador, Han Tae Song, made the comments at the UN-sponsored Conference on Disarmament in Geneva on Tuesday.

The Democratic People's Republic of Korea (DPRK) is "ready to use a form of ultimate means," Mr Han said.

He did not, however, say what these means will be.

He said: "The Washington regime fired up for political, economic, and military confrontation, [is] obsessed with the wild game of reversing the DPRK's development of nuclear force which has already reached the completion phase".

The Security Council had approved new sanctions on North Korea, but not the toughest measures sought by Donald Trump's administration.

U.S. wanted a ban on all oil imports and freeze of international assets of the government and its leader, Kim Jong-un. 

It also wanted China to cup supplies of fuel to North Korea, but that did not scale through.

"My hope is the regime will hear the message loud and clear and it will choose a different path," US disarmament ambassador Robert Woods told the Geneva forum.

Also Read: UN Approves New Sanctions Against North Korea

The Security Council believes the sanctions will ensure that North Korea faces consequences for every long-range ballistic missile and nuclear test.