"We did recently receive word that it was inconvenient for them to host a previously planned port call to Qingdao," said Randall Schriver, the assistant secretary of defense in charge of Asia.

Qingdao is a major port in eastern China that has long been considered strategic and has become a major hub for the country's "Belt and Road" global infrastructure initiative.

It is the latest cancellation by China, which earlier this month denied requests for two US Navy ships to dock in Hong Kong, which has been rocked by protests seeking to preserve the city's autonomy.

Port calls are largely exercises in public relations but also indicate a desire between powers to work together in an often tense region.

Schriver said that the United States hoped the latest port call could be rescheduled, saying the two militaries should try to enhance coordination and safety measures.

"Going forward, we want a US-China mil-to-mil relationship that plays a stabilizing role in the overall relationship," he said at the Center for Strategic and International Studies, a Washington think tank.

But he said that the United States remained concerned over Beijing's militarization of the South China Sea and fears that Beijing will crack down on dissent in Hong Kong.

Trade tensions have soared between the world's two largest economies, with President Donald Trump demanding that Beijing stop intellectual property theft and buy more US products.

Trump last week declared Chinese President Xi Jinping to be an enemy and announced tariffs on another $550 billion of imports before saying that negotiations would resume soon.