Chinese President Xi Jinping and North Korean leader Kim Jong Un have exchanged messages to reaffirm their intent to strengthen ties.
China's state-run Xinhua news agency says the messages were delivered by officials of the two sides when they met in Beijing on Monday.
The officials are Song Tao, the head of the International Department of the Chinese Communist Party's Central Committee, and the new North Korean ambassador to China, Ri Ryong Nam.
Xinhua quoted Xi as saying in the message that the traditional friendship between China and North Korea is a "precious treasure" shared by both.
He said China stands ready to work with North Korea "under the new situation."
Xinhua quoted Kim as pledging to strengthen and develop their relations into an envy of the world.
Their messages did not directly refer to the United States, but are seen as a bid to keep it in check by stressing the friendly ties between their countries.
The administration of US President Joe Biden has strongly criticized China over human rights and security issues. Washington has stressed trilateral cooperation with Japan and South Korea in dealing with North Korea.