Foreign Minister Yoshimasa Hayashi and his U.S. counterpart, Antony Blinken, on Friday shared "grave concern" over the Russian military buildup near Ukraine's border, with drills by Moscow fueling fears of a possible invasion, according to Japanese officials.

During their talks in Australia, Hayashi and Blinken also agreed to oppose any unilateral attempts to change the status quo in the East and South China seas, the officials said, as the two nations seek to bolster their security alliance to counter China's growing military and economic clout in the Indo-Pacific region.

Their second in-person meeting since Hayashi assumed his post in November was held on the sidelines of a gathering of foreign ministers of "the Quad" group, including Australia and India, in Melbourne the same day.