Japan and the Philippines on Saturday agreed to work toward signing a treaty designed to facilitate joint exercises and reciprocal visits of their military and other agencies amid China's increasingly assertive pursuit of sovereignty claims in regional waters claimed by the two.

The deal was struck during a meeting in Tokyo of their foreign and defense ministers, in which they expressed "serious concern" about the situation in the East and South China Seas and "strongly opposed" any action that may inflame tensions, according to their joint statement.

They also agreed that Russia's invasion of Ukraine has threatened the very foundation of rules-based international order and that the ramifications of the war go far beyond Europe.