The foreign ministers of Japan and China agreed Thursday that the two nations will maintain close communication "at all levels," the Japanese government said, as they have been exploring how to mend bilateral ties that often become tense.

Foreign Minister Yoshimasa Hayashi also aired "serious concern" over intensifying Chinese military activities near Japan, including those with Russia, during 50-minute phone talks with his Chinese counterpart Qin Gang, adding that Japanese public opinion on Beijing is very negative, according to the Foreign Ministry.

It was the first conversation between the two foreign ministers since Qin, a former ambassador to the United States, took the post in late December, succeeding Wang Yi.