Southeast Asia's top diplomats were set to kick off a major regional forum on Sunday with a firm focus on trying to ease tensions with China over a territorial row, amid warnings that failure could lead to conflict.
Toxic smoke from uncontrolled burning of Indonesia's enormous rainforests that has drifted across to neighbouring countries was also expected to be high on the agenda at the annual 10-member Association of Southeast Asian Nations (ASEAN) foreign ministers' meeting in Brunei's capital.
The talks will expand on Monday and Tuesday to include the United States, China, Japan, Russia and other countries across the Asia-Pacific, providing the platform for hectic face-to-face diplomacy on many of the world's hot-button issues.
As with previous regional gatherings, concerns over China's increasingly assertive actions in staking its claims to most of the South China Sea were set to dominate.
Setting the tone for the event, a powerful arm of China's state-run media warned the Philippines on Saturday that its defiance could lead to aggressive Chinese action.
"If the Philippines continues to provoke China... a counterstrike will be hard to avoid," said an editorial in the People's Daily, the mouthpiece of the ruling Communist Party.
ASEAN members the Philippines, Vietnam, Malaysia and Brunei, as well as Taiwan, also claim parts of the strategically vital South China Sea.
The waterway, which is believed to sit atop vast deposits of oil and natural gas, has long been regarded as one of Asia's potential military flashpoints and the escalating tensions in recent years has heightened concerns over potential battles for control.
The Philippines has been the most vocal of the other claimants to express alarm at China's growing assertiveness, which has included an increased Chinese naval presence in the area, and it reacted angrily to the latest threat from its more powerful neighbour.
"There is no place in the relations of civilised nations to use such provocative language. We call on China to be a responsible member in the community of nations," foreign ministry spokesman Raul Hernandez said in response to the People's Daily commentary.
ASEAN has been trying for more than a decade to secure agreement from China on a legally binding code of conduct that would govern actions in the South China Sea.
China has resisted agreeing to the code, wary of giving any concessions that may weaken its claim to the sea.
Nevertheless, Indonesian Foreign Minister Marty Natalegawa said ASEAN would continue to press its case with China in Brunei.
"We will be really zeroing in on the need for the code of conduct,"
Natalegawa told reporters on Saturday.
He said that a code, while not a "magic wand", would be an important tool in avoiding conflict.
"We need to manage and prevent miscalculations and unintended actions, reactions and (where) we have a huge furore and huge incident on our plate," he said.
"That is too huge a risk to have, this... sense of anarchy, a sense of lawlessness."
Meanwhile, US Secretary of State John Kerry is expected to hold a series of rapid-fire meetings with his counterparts from the world's major powers, including Russia's Sergei Lavrov and China's Wang Yi.
The United States has been frustrated in recent weeks by perceived Chinese and Russian help for fugitive intelligence leaker Edward Snowden, who is at Moscow's airport after being allowed to leave the Chinese territory of Hong Kong.
Within ASEAN, a key focus at Brunei will be Indonesia's forest fires, which this month caused Southeast Asia's worst air pollution crisis in years.
Natalegawa said on Saturday that the fires had been greatly reduced and were coming under control. (AFP)
