South Korea's top diplomat called Thursday for active diplomatic measures against North Korea over its nuclear test and missile launches in the latest push to punish Pyongyang for flouting UN resolutions.

The UN Security Council has been working on a fresh resolution to punish North Korea for its fifth nuclear test in September.

"It's time to consider taking more aggressive measures in diplomatic relations with North Korea," South Korean Foreign Minister Yun Byung-se said in an interview with Yonhap News Agency, citing article 41 of the UN Charter.

He also made his case for diplomatic actions in a separate address to the North Atlantic Council, NATO's top decision-making body, in Brussels.

Yun's comments are widely seen as thinly veiled appeals to the international community to either cut or downgrade diplomatic ties with North Korea.

Article 41 stipulates that the Security Council may decide what measures, not involving the use of armed force, are to be employed to effect its decisions, and it may call upon the Members of the United Nations to apply such measures. These may include complete or partial interruption of economic relations and of rail, sea, air, postal, telegraphic, radio, and other means of communication, and the severance of diplomatic relations.

Last month, Assistant US Secretary of State Daniel Russel said that Washington has asked countries around the world to "downgrade or sever" diplomatic and economic relations with North Korea in the wake of Pyongyang's fifth nuclear test.

The unusual move underscores the US commitment to further isolate the North from the international community.

A total of 164 countries have established formal diplomatic relations with Pyongyang, but many of them do not currently have an ambassador accredited to the North or a diplomatic mission in Pyongyang, according to a report last month by the National Committee on North Korea.

Twenty-four countries have embassies in Pyongyang, and the North has embassies in 46 countries, the report showed.

In 2014, Botswana severed diplomatic ties with North Korea after the UN Committee of Inquiry released a report accusing Pyongyang of serious human rights abuses such as holding thousands of people in political prison camps, abducting foreigners and forcing people to starve.

Yun also said that diplomatic pressure must be backed by credible military deterrence, noting diplomatic pressure is not enough to stop North Korea's nuclear programs.

His comments came as the UN Security Council has been working on a fresh resolution to punish the North for conducting its fifth nuclear test in September.

"The uncomfortable truth is that North Korea's deployment of nuclear weapons is nearing the final stage," Yun said.

Also Thursday, North Korea claimed that it "has now soared as a nuclear power possessed of powerful nuclear attack capabilities."

"The US will sooner or later face a shuddering reality in which their bayonet that targeted the life of the people of the (North) will boomerang on it," an unidentified spokesman of the North's Foreign Ministry said in an English-language statement carried by the official Korean Central News Agency.

Still, he did not elaborate on what he meant by boomerang on the US

It is not new for the communist country to boast progress in its nuclear and missile programs, but the latest claim came amid concerns that the North could be on track to develop a nuclear-tipped intercontinental missile that can reach the US mainland. (Yonhap)