Senior military officials from China and the United States held "in-depth" talks on Tuesday, Beijing's defence ministry said.
Washington and Beijing remain at odds on issues from trade to the status of self-ruled Taiwan and China's increasingly assertive approach in disputed maritime regions.
But they have sought to re-establish regular military-to-military talks in a bid to avoid those tensions escalating into conflict.
On Tuesday, Beijing's defence ministry said Wu Yanan, head of the Chinese army's Southern Theater Command had held "an in-depth exchange of views" with Samuel Paparo, Commander of the US Indo-Pacific Command.
The two officials discussed "issues of common concern", it added, in the first-ever talks of their kind.
The Southern Theater Command is responsible for the Beijing military's activities in the South China Sea, where Chinese vessels have engaged in a series of high-profile confrontations with Philippine ships in recent months.
China claims almost all of the economically vital body of water despite competing claims from other countries and an international court ruling that its assertion has no legal basis.
Tuesday's high-level military dialogue between the geopolitical rivals comes on the heels of the first visit to China by a US national security advisor since 2016.
Top White House aide Jake Sullivan visited Beijing last month, where he held talks with senior army official Zhang Youxia.
Sullivan's meeting with Zhang saw the officials agree to hold a call between the two sides' theatre commanders in the near future, the White House said.
The top aide also raised the importance of "freedom of navigation" in the South China Sea, where Beijing and Manila have clashed in recent months, and "stability" in the Taiwan Strait, Washington said.
Zhang, in turn, warned that the status of the self-ruled island was "the first red line that cannot be crossed in China-US relations".
"China demands that the US halts military collusion with Taiwan, ceases arming Taiwan, and stops spreading false narratives related to Taiwan," Zhang added.
He also asked the US to "work with China to promote communication and exchanges between the two militaries and jointly shoulder the responsibilities of major powers".
