Japan's concerns over Chinese military posturing in the East and South China seas are shared by many other countries, Tokyo's Foreign Minister Fumio Kishida said Monday.
"Honestly speaking, not only the Japanese people but also states of the Asia-Pacific region and the international community have big worries," Kishida said ahead of his visit to Beijing this week.
China has shown a "fast-paced and opaque increase in military spending, and unilateral actions to change the status quo in the East and South China seas."
Japan's relations with China are strained over differing views of 20th-Century wartime history and a territorial spat over a group of uninhabited islets in the East China Sea.
The Japanese-administered Senkaku Islands are also claimed by China and Taiwan, where they are known as Diaoyu and Tiaoyutai, respectively.
The issue is to feature during talks between Kishida and his Chinese counterpart Wang Yi, Kyodo News agency reported.
China has been reclaiming land on islands and reefs in the South China Sea, a key shipping lane believed to be rich in mineral and marine resources.
Beijing claims nearly all of the South China Sea, including small islands hundreds of kilometres from its southern coast, amid competing claims by Brunei, Malaysia, the Philippines, Taiwan, and Vietnam.
The foreign ministers of the Group of Seven (G7) leading industrialized expressed "strong opposition to any intimidating, coercive or provocative unilateral actions that could alter the status quo and increase tensions," in a statement issued after a Japan-hosted meeting this month.
China responded by summoning the Japanese ambassador and the deputy ambassadors of all other G7 embassies the following day.