South Korea and China plan to hold high-level security talks in Beijing later this month, a diplomatic source with knowledge of the matter said Monday, as Seoul seeks to persuade Beijing to do more in dissuading North Korea from conducting its fourth nuclear test.

South Korea's Presidential Security Adviser Kim Jang-soo is scheduled to visit Beijing and hold talks with Chinese State Councilor Yang Jiechi, China's top foreign policymaker, in the fourth week of this month, the source said on the condition of anonymity.

The high-level security talks, the second of their kind since November last year, come as North Korea has threatened to carry out its fourth nuclear test since late March. South Korean Defense Minister Kim Kwan-jin said last week that the North was making final preparations to detonate an atomic device.

"The two sides are in the process of setting the agenda for the 2nd Korea-China High-Level Security Dialogue," the source said, adding the agenda is expected to focus on how to get North Korea to change its ways.

This month's Beijing talks between Kim and Yang are also in part aimed at making preparations for a visit by Chinese President Xi Jinping to South Korea, which is widely expected to take place in the coming weeks, according to the source.

China is North Korea's last-remaining key ally and its economic lifeline, but Beijing's leverage with Pyongyang has been called into question. North Korea conducted its third nuclear test in February last year after snubbing China's warnings.

Amid heightened tension, North Korea renewed its threat of a nuclear test on Saturday. In a commentary, the North's official Rodong Sinmun newspaper said Pyongyang "clarified its resolute stand that it would take countermeasures including a nuclear test to protect the sovereignty and dignity of the DPRK (North Korea)."

"No one has the right to criticize it," it said. (Yonhap)