Southeast Asian leaders will hold talks with a Myanmar junta representative at a summit on Wednesday as they try to kick-start faltering diplomatic efforts to broker an end to the country's bloody civil war.

Rising tensions in the disputed South China Sea will also be on the agenda at the Association of Southeast Asian Nations (ASEAN) gathering, after months of violent clashes between Chinese vessels and Philippine and Vietnamese fishermen.

ASEAN has tried to no avail for three years to find a negotiated solution to the Myanmar crisis, which has left thousands dead and forced millions to flee their homes.