Japanese Prime Minister Fumio Kishida on Wednesday stressed to Southeast Asian leaders his country's strong opposition to challenges to a free and open maritime order, underscoring regional concerns about China's growing military clout.

Kishida took part in a virtual summit with leaders of the Association of Southeast Asian Nations (Asean), who earlier discussed concerns about militarisation and confrontation in the South China Sea and called for the conclusion of an Asean-China code of conduct "consistent with international law".

US President Joe Biden will join the...