BEIJING, China: In a new sign of strain between the United States and China, Beijing has rejected a request from the U.S. for a meeting between their defense chiefs at an annual security forum in Singapore this weekend.

"Overnight, the PRC informed the U.S. that they have declined our early May invitation for Secretary (Lloyd) Austin to meet with PRC Minister of National Defense Li Shangfu in Singapore," the Pentagon said in a statement to the Wall Street Journal, referring to China by the initials of its official name, the People's Republic of China.

Li has been under U.S. sanctions since 2018 over the purchase of combat aircraft and equipment from Russia's main arms exporter, Rosoboronexport.

The Pentagon said it believed in open communication "to ensure that competition does not veer into conflict."

The prospect of a meeting was being closely watched, given regional security tensions and trade disputes that have derailed plans for re-engagement by the world's two largest economies.

China's foreign ministry has blamed the United States for its decision, claiming that Washington was "well aware" of the reasons behind the lack of military communications.

"The U.S. side should ... immediately correct its wrong practices, show sincerity, and create the necessary atmosphere and conditions for dialogue and communication between the two militaries," foreign ministry spokesperson Mao Ning told reporters at a briefing.

Singapore-based security analyst Ian Storey said China's decision to shun Austin did not bode well.

"At a time of rising U.S.-China tensions, General Li's refusal to meet his American counterpart will fray regional nerves even further," Storey said, as quoted by Reuters.

Austin and Li will be in Singapore to attend the annual Shangri-la Dialogue, an informal gathering of defense officials and analysts, which also plays host to a string of side meetings.