ASEAN leaders skirt confrontation over sea

South-East Asian leaders have urged Chinese Premier Li Keqiang to follow international laws in resolving disputes in the South China Sea.

South-East Asian leaders have urged China's premier (L) to resolve disputes in the South China Sea. (AAP)

South-East Asian leaders have urged "stoical" Chinese Premier Li Keqiang to follow international laws in resolving disputes in the South China Sea.

But leaders of the 10-country Association of South-East Asian Nations (ASEAN) at a summit in Vientiane did not press Beijing to comply with an international arbitration court ruling that rejected Beijing's claims to almost the entire sea.

"What was underlined by countries like Singapore and the Philippines was the importance of the rule of law and adhering to international bodies that govern this," Philippine Communications Secretary Martin Andanar said.

Li "was stoically listening" as Philippine President Rodrigo Duterte discussed his views on the disputes in the South China Sea, a key shipping lane believed to be rich in marine and mineral resources, Andanar said.

"His face did not have any reaction," he added.

Li told the ASEAN leaders that the South China Sea issue "should not represent the main relations" between the regional bloc and Beijing and that ties were moving in a "positive direction."

The meeting occurred amid concern that China is preparing for fresh construction work in the South China Sea after 10 ships were spotted near the Scarborough Shoal, including four vessels that look like barges.

As the leaders met, the Philippine Defence Department released new surveillance photos of 10 ships "to announce that we are aware of any and all movements in the area," Philippine presidential spokesman Ernesto Abella said.

In a bid to ease tensions over the territorial disputes, ASEAN and China adopted a protocol and a communication hotline among foreign ministers to avoid clashes resulting from unplanned encounters.

Singapore Prime Minister Lee Hsien Loong stressed the need for guidelines for the Code for Unplanned Encounters at Sea and for a communication hotline to be established, Andanar said.

Lee added that a framework for a code of conduct in the South China Sea between ASEAN and China should be initiated this year, he said.

In a statement to be issued at the end of the meeting, the leaders were expected to express serious worries over Chinese land reclamation in the South China Sea.