North Korean leader Kim Jong-un called on the ruling party's propaganda officials to wage a battle in rooting out "evil spirits" of anti-socialism and bring fundamental change in their ideological work, state media reported Tuesday.

In a letter sent to officials serving in the information field of the ruling Workers' Party (WPK) who were present at a workshop in Pyongyang the previous day, Kim stressed the need to "concentrate the ideological campaign on anti-socialist and non-socialist practice in a minute way," according to the Korean Central News Agency (KCNA).

"Mass oppressive offensive and social struggle atmosphere should be raised continuously and methodologically to beat all kinds of negative phenomena that gnaw away at our revolutionary position and crush them without mercy," Kim wrote.

He then noted "the Party information work is a keystone in sweeping away evil spirits of anti-socialism and non-socialism finding their way into the heads of the people."

Kim emphasized the party officials should become "powerful loudspeakers and hi-fi amplifiers" in spreading the Party Central Committee's ideas "down to the lowest unit correctly in time."

"The ideology-first principle is just the fundamental key to emerging victorious from difficult situations and a way of revolution peculiar to the WPK," he was quoted as adding.

He urged officials at the Information and Publicity Department of the ruling party's Central Committee to become a "control tower" of the party's ideological front.

An official at South Korea's Ministry of Unification, which handles inter-Korean affairs, said the latest workshop appears to be part of Pyongyang's efforts to tighten discipline and unity among party officials.

"The workshop appears intended to solidify internal unity and urge the (thorough) implementation of the five-year plan unveiled at the eighth party congress," the official told reporters on background.

North Korea has been pushing for accelerating economic development under the five-year campaign announced at the congress held in January last year, during which Kim admitted to a failure in his previous initiative amid crippling sanctions and a protracted border closure over COVID-19. (Yonhap)