The three-day trip will be Lee's first to Russia as prime minister.

During the visit, Lee plans to deliver a keynote speech at the forum to outline the New Northern Policy by which the government of President Moon Jae-in is seeking to strengthen relations with Russia, Mongolia and other northern countries.

Lee will also attend a forum of businesspeople of the two countries, the office said.

During a meeting with Putin on Wednesday, Lee plans to discuss ways to further strengthen bilateral relations and increase cooperation in efforts to bring permanent peace to the Korean Peninsula. The two sides are also expected to check on how June's summit agreement between Moon and Putin is being implemented, his office said.

Lee also plans to hold meetings with Abe and Battulga on Tuesday.

After arriving in Vladivostok, Lee attended a dinner to promote friendly relations between the South and Russia, along with officials in the Maritime Province, South Korean residents and ethnic Koreans living in the region.

"President Moon will visit North Korea next week for his third inter-Korean summit. High-level talks between the United States and North Korea are also likely to be resumed," the prime minister said.

Lee also stressed that the scope of cooperation between Seoul and Moscow will expand and their ties will deepen. (Yonhap)