North Korea marked the 70th anniversary of the Korean War armistice Thursday with Chinese and Russian delegations, in an apparent show of unity amid their rivalries with the United States.

Pyongyang could stage a military parade early Thursday morning, according to sources familiar with inter-Korean relations.

The delegations sent by Beijing and Moscow are the first known foreign groups to be invited to North Korea since the country's 2020 COVID border closure.

Russian Defense Minister Sergei Shoigu, who is leading Moscow's delegation, held talks with his North Korean counterpart Kang Sun Nam and agreed to strengthen bilateral defense cooperation, calling Pyongyang an "important partner," Russia's Defense Ministry said Wednesday.

The Chinese group is headed by Li Hongzhong, a member of the ruling Communist Party's Political Bureau.

Russian Defense Minister Sergei Shoigu (3rd from L) is greeted by his North Korean counterpart Kang Sun Nam (2nd from L) and others upon his arrival at Pyongyang International Airport in Pyongyang, North Korea, on July 25, 2023. (KCNA/Kyodo)

There is a possibility that Shoigu and Li will meet with North Korean leader Kim Jong Un during their stay. If realized, their talks will be the first contact between Kim and senior foreign officials since the leader met with then U.S. President Donald Trump at the Demilitarized Zone dividing the two Koreas on June 30, 2019.

Since January 2020, North Korea has maintained almost entirely closed borders to stem the spread of the novel coronavirus.

Pyongyang claims the 1950-53 Korean War ended in its victory over U.S.-led allied forces.

In the conflict, which began on June 25, 1950, with a North Korean invasion aimed at unification under the Communist regime, the U.N. forces led by the United States fought alongside South Korea against the North, supported by China and the Soviet Union.

Ahead of the anniversary, Kim visited a cemetery for fallen Chinese troops who "unsparingly dedicated their precious lives to the righteous war of the Korean people to repel the imperialist aggression," North Korea's official Korean Central News Agency said.

To pay tribute to them, the leader placed a flower before the grave of Mao Anying, the eldest son of China's founder Mao Zedong, the report said.

Chinese Foreign Ministry spokeswoman Mao Ning welcomed Kim's move Wednesday, saying it shows that North Korean people "cherish the great achievements" of the Chinese troops and reflects "the traditional friendship" between Beijing and Pyongyang.

Calling the two countries "friendly neighbors linked by mountains and rivers," Mao pledged that China will promote peace and stability on the Korean Peninsula.