The two Koreas are poised to face off at the UN this week as tension continues to intensify following Pyongyang’s latest nuclear test, with Seoul ramping up its push for stiffer international sanctions.

South Korean Foreign Minister Yun Byung-se arrived in New York over the weekend to deliver a keynote address at the General Assembly and hold some 15 rounds of bilateral and multilateral talks with his counterparts from the US, Japan and other countries.

Atop his agenda is rallying member states behind ongoing efforts to formulate a new UN Security Council resolution following the North’s fifth atomic blast on Sept. 9.

Yun will kick off the drive with a tripartite session with US Secretary of State John Kerry and Japanese Foreign Minister Fumio Kishida and a two-way meeting with Kishida, both scheduled for Sunday afternoon, during which he is also expected to coordinate their independent punitive steps. 

“We’re currently in in-depth consultations with UNSC members and other nations on how to complement Resolution 2270, which was approved after the fourth nuclear test, and how to make North Korea feel pain from its latest nuclear test,” Yun told reporters shortly before his departure from Incheon International Airport late Saturday.

“From the UN level, issues like refugees and climate change are critical. On our side, I will focus on three areas -- North Korea’s nuclear and missile threats, which is one of the gravest challenges not just to the peninsula but also in Northeast Asia and the international community, as well as its severe human rights violations.”

North Korean Foreign Minister Ri Yong-ho is likely to defend the country’s much decried nuclear program through a speech at the assembly this Saturday.

During a meeting of the Non-Aligned Movement in Venezuela last Thursday, he argued the newest underground explosion was a “legitimate, inevitable self-defensive measure” to counter “constant threats” from the US.

Pyongyang is ready for a “counterattack against US provocations” including last Tuesday’s flying of two B-1B supersonic bombers over the peninsula in a display of force.

The recent experiment signaled the communist state’s progress in its nuclear development, as it showed the largest explosive power to date.

Tension is running high given the lingering possibility of an additional blast. Citing commercial satellite imagery from Sept. 15, the US-Korea Institute at the Johns Hopkins School of Advanced International Studies said Friday that Pyongyang may detonate further devices at the unused tunnels at its Punggye-ri complex, echoing the South Korean military’s assessment days earlier.

The five permanent UNSC members, including China and Russia, also issued a joint statement condemning the recent North Korean provocation after their two-day conference in Washington late Friday.

It called for a “complete, verifiable, and irreversible denuclearization of the Korean Peninsula in a peaceful manner,” reaffirming their commitment to peace and stability in the region as well as the 2005 denuclearization accord of six-party talks.

By Shin Hyon-hee (heeshin@heraldcorp.com)