A top foreign affairs aide to South Korean President Park Geun-hye attended an annual international security conference in Russia and held a series of bilateral talks on North Korea and other issues, the foreign ministry said Wednesday.

Ju Chul-ki, the senior presidential secretary for foreign affairs and security, has been in Russia's Far Eastern city of Vladivostok since Tuesday to attend a fourth meeting of ranking security officials from the United States, China and other major countries.

The three-day meeting that kicked off on Tuesday brought together about 300 delegates from some 50 countries, including all five dialogue partners of North Korea in six-party talks aimed at ending Pyongyang's nuclear program, according to the ministry.

In his speech during a high-level meeting session, Ju stressed the need to strengthen pan-Northeast Asian cooperation to effectively deal with terrorism, money laundering and nuclear safety, among other issues, the ministry said in a statement.

On the sidelines of the meeting, Ju held bilateral talks with senior officials from the U.S., China, Japan and Russia to discuss the security circumstances of the Korean Peninsula and other issues of mutual concern.

Ju's trip coincided with a trip to Russia by North Korea's chief nuclear negotiator, First Vice Foreign Minister Kim Kye-gwan. Kim left for Russia on Tuesday, according to Pyongyang's state media.

It was unclear if Kim plans to attend the Vladivostok conference. But officials at Russia's Foreign Ministry said Kim plans to visit Moscow Thursday for talks on the standoff over Pyongyang's nuclear program.

The Vladivostok meetings followed Seoul's bilateral and multilateral talks in Brunei on the occasion of the ASEAN Regional Forum earlier this week with the member countries to build a united front against the North's nuclear ambitions.

In a chairman's statement, they, along with 21 other Asia-Pacific states and the European Union, called on Pyongyang to denuclearize after fully abiding by its past pledges to end its nuclear program. (Yonhap News)