North Korean leader Kim Jong-un has visited a tank unit bearing "Seoul" in its name for being the first to enter the South Korean capital during the Korean War, praising the unit as a "model for the entire army," state media said Monday.

Kim visited the Seoul Ryu Kyong Su Guards 105th Tank Division and the affiliated First Tank Armored Infantry Regiment on Sunday, the Korean Central News Agency said.

"The division ... was the first to charge into Seoul and fly the flag of the DPRK on the puppet capitol building and performed distinguished feats in many battles during the past Fatherland Liberation War, thus adding the title of guards and Seoul to its brilliant name," the KCNA said.

Kim touted the unit as "the symbol of the heroic and brave spirit of" the North's military, saying it "should hold high the banner as befitting a model of the entire army in the ongoing struggle witnessing the intensive training for finishing war preparations."

"He set forth important tasks, guidelines for strengthening in every way the combat preparations and combat efficiency of the unit including the issue of arming the tank crews with overwhelming ideological and moral strength and thoroughly training them in military technical and physical aspects and getting combat technical equipment always ready for action," the KCNA said.

During the visit, Kim was also briefed on the unit's attack and defense operation plans and looked around its facilities, such as its cafeteria and medical wards, it added.

The visit came as the North has been ramping up tensions after defining South Korea as a "primary foe and invariable principal enemy" and codifying its commitment to "completely occupying" the South in the event of a war in the country's constitution.

Last week, North Korea fired short-range ballistic missiles in violation of UN Security Council resolutions and conducted a ground jet test of what it said was a solid-fuel engine for a new type of intermediate hypersonic missile. (Yonhap)