North Korea will be "further isolated and abandoned" by the international community if it goes ahead with its threat of conducting a fifth nuclear test, South Korean Foreign Minister Yun Byung-se warned Thursday.

Yun said the South Korean government is closely watching the latest developments in North Korea, including the possibility of another nuclear test, and putting its diplomatic resources to work with the international community to deter North Korea from advancing its nuclear capability and conducting further provocations.

"If there are further provocations, North Korea will be further isolated and abandoned by the international community," Yun told reporters in Beijing after attending a foreign ministers' meeting at a regional security forum led by Russia and China.

 "Including Russia and China, the international community shared our views that they should join forces and sternly deal with it if North Korea conducts another nuclear test," Yun said.

North Korea conducted its fourth nuclear test in January and launched a long-range rocket in February, prompting the U.N. Security Council to tighten sanctions against the isolated North.

Despite international pressure, there have been signs that North Korea may carry out another nuclear test ahead of its key party congress set to kick off on May 6.

The foreign ministers attending the regional security gathering in Beijing on Thursday called for North Korea to give up its nuclear weapons program "in a complete, verifiable and irreversible manner."

It was the first time that the foreign ministers' meeting of the Conference on Interaction and Confidence Building Measures in Asia (CICA), in its fifth time meeting, adopted a declaration that calls for North Korea's denuclearization, Yun said.

The CICA ministers also urged North Korea not to conduct more nuclear and ballistic missile tests.

Thursday's declaration of the CICA meeting showed signs of the further isolation of North Korea because most of its member states have enjoyed friendly relations with the North, Yun said.

Founded in 1992, the CICA has 26 member states, mostly non-Western countries such as Russia, China, Kazakhstan and Mongolia.

Yun is the first South Korean foreign minister to attend the foreign ministers' meeting of the CICA since South Korea joined the gathering in 2006.

(Yonhap)