Concerns over China's aggressive behavior in the South China Sea top the agenda in the first regional summit hosted by Myanmar, which is hoping to demonstrate the progress it's made since emerging from a half-century of brutal military rule.
A standoff between Chinese and Vietnamese ships near the Paracel Islands is putting a fresh spotlight on long-standing and bitter maritime disputes.
The stakes are high — it's one of the world's most important shipping lanes — but some members of the Association of Southeast Asian Nations are wary of upsetting the regional powerhouse.
Leaders are also expected Sunday to discuss tensions on the Korean Peninsula and Thailand's political crisis.
This is the first time Myanmar is hosting a summit of regional leaders since it joined the 10-member bloc in 1997.