"Both sides agreed to boost high-level contact and exchange in the political field, actively promote cooperation in the fields of economy and humanitarianism, bolster up mutual support and collaboration in tackling the issue of the Korean peninsula and on the international arena," the KCNA said.

"A 2019-2020 plan of exchange between the two Foreign Ministries was signed following the negotiations," it added.

Observers speculate that "high-level contact" could mean a possible trip to Moscow by North Korean leader Kim Jong-un for his first summit with Russian President Vladimir Putin.

Pyongyang has been stepping up its diplomacy with Russia since the collapse of the summit between Kim and U.S. President Donald Trump last month.

Experts see it as an attempt to solidify relations with its neighboring countries for future nuclear talks with Washington, while at the same time possibly securing economic assistance.

Im Chon-il's visit to Russia came on the heels of trips by two other senior North Korean officials.

Earlier this month, North Korea's Minister for External Economic Affairs Kim Yong-jae met with Russian Minister for the Development of the Far East Alexander Kozlov to discuss cooperation on trade and the economy.

Han Man-hyok, vice department director of the Central Committee of the North's ruling Workers' Party, also visited Russia recently to attend a photo exhibition organized to mark the 70th anniversary of late North Korean founder Kim Il-sung's official state visit to Moscow. (Yonhap)