Southeast Asian leaders are meeting at an annual forum that will focus on the civil war in Myanmar and territorial tensions in the South China Sea, two challenges that have long tested the bloc's credibility.

Vietnam, the Philippines, Malaysia and Brunei all have overlapping claims with China, which claims sovereignty over virtually all of the South China Sea and has become increasingly aggressive in attempts to enforce them. Indonesia has also expressed concern about what it sees as Beijing’s encroachment on its exclusive economic zone.

Rising tensions in the disputed South China Sea will also be on the agenda at the gathering of the Association of Southeast Asian Nations in Laos.