Japanese Prime Minister Shinzo Abe told a regional security forum that Tokyo would offer its "utmost support" to Southeast Asian countries - several locked in maritime rows with Beijing - in their efforts to protect their seas and airspace, as he pitched his plan for Japan to take on a bigger international security role.
Abe, in his keynote address on Friday at the Shangri-La Dialogue for security officials and experts from Asia, also stressed the need for all countries to respect international law - often code for criticising China's assertive military stance.
Tensions have ratcheted up in the region, where Japan has a festering dispute with China over tiny isles in the sea between the two Asian economic giants. Beijing and several Southeast Asia countries are at odds over rival claims to the oil-and-gas rich South China Sea.
"Japan will offer its utmost support for the efforts of the countries of ASEAN as they work to ensure the security of the seas and the skies, and thoroughly maintain freedom of navigation and freedom of overflight," Abe told the forum.
Abe's address, the first to the forum by a Japanese leader, coincides with his controversial push to ease restrictions of the post-war, pacifist constitution that have kept its military from fighting overseas since World War Two.
"Japan intends to play an even greater and more proactive role than it has until now in making peace in Asia and the world something more certain," he said. (Reporting by Linda Sieg and Masayuki Kitano; Editing by Nick Macfie)