When the United States imposed sanctions on China's military this fall, China retaliated by canceling Defense Secretary Jim Mattis' plans to meet his counterpart in Beijing. But just days later, a Chinese general visited the Pentagon with a reassuring message: Beijing valued the importance of military ties between the two countries.

In the previously unreported visit, Huang Xueping arrived on Oct. 10 to see Mattis' aides, but the secretary briefly met him in the hallway with a message for Chinese Defense Minister Wei Fenghe. The two were still going to be at a security conference in Singapore later in October, and Mattis told Huang he looked forward to meeting Wei there, said Randall Schriver, the Pentagon's top Asia policy official.

Relations between the world's two largest economies have plumbed new depths under President Donald Trump amid a bitter trade war and disagreements over Taiwan, the South China Sea, and other geopolitical flash points.