South Korea and external stakeholders in the Korean Peninsula such as China and the U.S. are moving swiftly to ensure regional security, especially since the mourning period for the late North Korean leader Kim Jong-il ended on Thursday, sources said.

South Korea, which is still technically at war with North Korea, is trying to ensure a soft landing of the post-Kim Jong-il regime by not aggravating Pyongyang.

A government official here said the Seoul government will focus on maintaining stability on the peninsula and making goodwill gestures toward the North.

After Kim’s death, Seoul sent a message of condolences to the North Korean people and allowed two private delegations to visit the North to pay respects to the late Kim.

“With North Korea in a transition of leadership, uncertainty over security and geopolitics has greatly increased,” a Unification Ministry official told local media.

“We’re putting top priority on keeping stability and order on the Korean Peninsula. We will closely monitor developments and maintain stability.”

Observers do not rule out the possibility that severe instability of the North Korean regime could lead to its collapse or an outbreak of hostilities.

Alexander von Rosenbach, senior analyst on security at IHS Jane’s, noted the two Koreas are on high alert during the transitional period in the North.

“The South Korean army is half the size of North Korea’s million-man army, whose soldiers would be determined fighters despite being poorly trained and equipped. While nuclear capabilities are often on the spotlight, it is their inventiveness and the sheer size of the military and traditional capabilities that are the bigger threat,” Rosenbach said in an e-mail.

However, more likely is a period of calm as the North Korean military resolves its new internal power structures, he said.

Regarding nuclear security on the peninsula, both Washington and Pyongyang seem to be willing to hold a third round of bilateral talks soon, said Hong Hyun-ik, director of Security Strategy Studies at the Sejong Institute.

“Although Kim Jong-un may not be able to open up the country actively, he should revive the North Korean economy. To do so, North Korea is highly likely to reach out for the U.S.,” he said.

Just hours before the announcement of North Korea’s leader Kim Jong-il’s death on Dec. 19, Washington and Pyongyang reportedly reached a tentative agreement on U.S. aid for the state in exchange for North Korea’s suspension of its nuclear program.

Hong said relations between the two Koreas may not automatically improve in the event U.S.-the North relations improve.

“If Seoul keeps demanding an apology for the torpedoing of a South Korean navy vessel Cheonan and the shelling on the northwestern border island of Yeonpyeong, the inter-Korean relationship could be dormant again,” he said.

Worsened inter-Korean relations could prompt Pyongyang into mounting another provocation, he warned.

The U.S., China and Japan are also moving quickly to ensure stability of the Northeast Asian region.

U.S. Assistant Secretary of State Kurt Campbell is expected to visit Korea in early January to discuss the North Korean issue, while senior diplomats from Korea, the U.S. and Japan plan to hold a trilateral meeting in Washington in mid-January, according to the Foreign Ministry.

Next week, Campbell plans to visit not only Korea but also China and Japan, other foreign ministry officials said.

By Kim Yoon-mi (yoonmi@heraldcorp.com)