China's vice foreign minister was in Pyongyang on Friday for a meeting with his North Korean counterpart.
China and Russia are North Korea's traditional allies, and Washington warned last year that military ties between Pyongyang and Moscow were "growing and dangerous".
The United States has called on Beijing -- the North's biggest economic benefactor -- to restrain Pyongyang.
"The Foreign Ministry delegation of the People's Republic of China, headed by Comrade Sun Weidong, Vice Minister of Foreign Affairs, arrived in Pyongyang on the 25th," the North's official Korean Central News Agency said Friday.
AFP photos showed Weidong and his delegation meeting with North Korean Vice Foreign Minister Pak Myong Ho and others at the People's Palace of Culture in the capital.
Sun's visit comes as US National Security Advisor Jake Sullivan was set to meet Chinese Foreign Minister Wang Yi on Friday and Saturday in Thailand, as the two powers seek to improve relations after years of tensions.
Earlier this month, North Korean leader Kim Jong Un said Pyongyang and Beijing had designated 2024 as the "year of DPRK-China friendship," using the acronym of the North's official name.
The two countries "will further promote exchange and visits in all fields, including politics, economy and culture" this year, and add "a new page to the history of the DPRK-China relations," Kim said in his message to Chinese President Xi Jinping, according to KCNA.
Kim's friendly message to Xi stood in stark contrast to his recent, dramatically aggressive rhetoric towards the South.
Earlier this month, Kim declared Seoul his country's "principal enemy", jettisoned agencies dedicated to reunification and outreach and threatened war over "even 0.001 mm" of territorial infringement.
As the threat from the nuclear-armed North grows, South Korean President Yoon Suk Yeol has pulled Seoul closer to long-standing ally Washington.
While Tokyo, Seoul and Washington have held joint military exercises against the growing North Korean threats, Beijing last year sent senior officials to attend Pyongyang's military parades.
As permanent members of the UN Security Council, both China and Russia have been obstructing the efforts led by Washington to impose stricter sanctions on North Korea in response to its increased weapons testing activities in recent months.
Kim also successfully put a spy satellite into orbit late last year, after receiving what Seoul said was Russian help, in exchange for arms transfers for Moscow's war in Ukraine.
