South Korean President Moon Jae-in's top security aide held talks Monday with high-level North Korean delegates to the PyeongChang Winter Olympic Games, informed sources said.

Chung Eui-yong, chief of the National Security Office, met the North Korean delegates for lunch at a Seoul hotel, according to the sources. Other details of the meeting could not immediately be confirmed.

The meeting came one day after Moon met Kim Yong-chol, the chief of the eight-member North Korean delegation, who told Moon that his country was willing to hold talks with the United States.

Inter-Korean dialogue was resumed last month to discuss the North's participation in the Feb. 9-25 Winter Olympic Games. South-North talks were last held in December 2015.

Monday's meeting between Chung and the North Korean officials also involved Seoul's chief negotiator in six-way talks on ending North Korea's nuclear ambition, Lee Do-hoon, according to the sources.

The six-party denuclearization talks have been stalled for nearly a decade. North Korea staged its sixth and most powerful nuclear test so far in September 2017.

The North Korean delegation is set to return home Tuesday.(Yonhap)