The AMM 50 and related meetings will last until August 8.
Attempts to hammer out such guidelines have been ongoing for years, and ASEAN members and Beijing announced Sunday that they had agreed a framework for a future code of conduct, but formal negotiations are not expected to start until November, according to CNN Philippines.
Several Asean diplomats said that among the members who pushed for a communique that retained the more contentious elements was Vietnam, which has competing claims with China over the Paracel and Spratly archipelago and has had several spats with Beijing over energy concessions.
Criticising ongoing "land reclamation, construction of outposts, militarisation of disputed features" in the disputed sea, the trio said any code of conduct must be "legally binding, meaningful and effective", a demand noticeably absent from the ASEAN statement.
Manila: The United States, Australia and Japan on Monday denounced Beijing's island-building and militarisation of the South China Sea, in contrast to the increasingly tepid response from Southeast Asian nations over the festering issue.
Japan has been calling on parties concerned to faithfully follow the July 2016 ruling by the Permanent Court of Arbitration in The Hague, the Netherlands, that rejected China's claims in its territorial dispute with the Philippines in the South China Sea.
A Philippine government spokesman says Southeast Asian foreign ministers have endorsed the framework for a long-sought code of conduct in the disputed South China Sea.
"We could have done more to push China to agree to a much stronger document, holding claimant states more accountable", said one Asean diplomat.
"The atmosphere of this year is different from the past", Wang said. "I mean it's really very insubstantial anyway", Mr Batongbacal said, expressing doubt that Asean and China will be able to come up with anything concrete in the next few years. But China, which claims virtually the entire South China Sea, is unlikely to allow the negotiations to move in that direction.
Adding to the drumbeat of criticism, the commander of USA forces in the Pacific, Adm. Harry Harris, said Monday that the code of conduct negotiations with an "aggressive" China will be a key challenge for the region.
As an important regional organization, ASEAN has become a major force in promoting regional integration and maintaining regional peace and stability, Wang said.
"Vietnam is adamant, and China is effectively using Cambodia to champion its interests".
The 10 foreign ministers of the Association of Southeast Asian Nations reiterated in a joint statement Saturday their grave concerns over the escalation of tensions on the Korean Peninsula due to the North's two ICBM tests last month, saying the launches threaten world stability.
The current ASEAN chairman, Philippine President Rodrigo Duterte, has made it a priority to fix bilateral ties with China, which has rejected an global court's ruling in 2016 that invalidated its claim to the entire sea region.