BEIJING - China on Saturday expressed "strong concern and firm opposition" to a joint statement released after a U.S.-Japan summit in which they voiced anxiety over several matters related to Beijing such as Xinjiang, Hong Kong, Taiwan and the nearby waters.

U.S. President Joe Biden and Japanese Prime Minister Yoshihide Suga at the summit on Friday agreed to further their cooperation across regional security, technology and other areas, committing to an alliance that will face up to the challenges posed by China.