SINGAPORE -- South Korean President Moon Jae-in plans to meet with US Vice President Mike Pence on the sidelines of a regional summit in Singapore on Thursday, the presidential spokesman said Wednesday.

The one-on-one meeting comes as North Korea's denuclearization process has made little headway in recent weeks, with the planned high-level talks between the US and the North having been called off at the last minute last week.

Pence also said in an article contributed to the Washington Post last week that the US will continue to "exert unprecedented diplomatic and economic pressure on North Korea."

Moon and Pence last met in February when Pence visited South Korea to attend the PyeongChang Winter Olympics.

Earlier in the day, South Korea's main intelligence agency said that the North is believed to be continuing nuclear and missile activity even after the historic summit between US President Donald Trump and North Korean leader Kim Jong-un in June.

Asked for comment on the report, presidential spokesman Kim Eui-kyeom said that ongoing negotiations with the North are aimed at "halting such activity and realizing complete denuclearization."

Kim also said that Moon plans to meet one-on-one with Chinese President Xi Jinping in Papua New Guinea on Saturday on the sidelines of this year's summit of the Asia Pacific Economic Cooperation forum involving Pacific Rim nations. (Yonhap)