JAKARTA, Sep. 5 (AFP) - Southeast Asian leaders will gather Tuesday in Indonesia for talks set to be dominated by the crisis in Myanmar and China's growing assertiveness in the South China Sea.

The Association of Southeast Asian Nations (ASEAN) summit will be followed by talks with Beijing, Washington and other powers where US Vice President Kamala Harris will seek to push back on China's assertiveness in the contested waterway in place of President Joe Biden.

The 10-nation bloc has long been decried as a toothless talking shop and divided members are struggling to find a united voice on the Myanmar crisis since a 2021 coup overthrew the member country's democratically elected government.

A spate of bilateral meetings with world powers Wednesday will be followed by the 18-nation East Asia Summit on Thursday where heavyweights Biden, Chinese President Xi Jinping and Russian President Vladimir Putin will be absent.

Representing Beijing and Moscow will be Chinese premier Li Qiang and Russian Foreign Minister Sergei Lavrov.

Before that, ASEAN members will gather to hash out a declaration that accommodates all members' positions on Myanmar, where the military coup unleashed a bloody crackdown on dissent.

A draft of the final communique seen by AFP left blank a Myanmar section, belying the lack of consensus.

Chair Indonesia has pushed for Myanmar's junta -- which is barred from the bloc's high-level meetings -- to enforce a five-point plan agreed two years ago to end the violence and restart negotiations.

But those efforts have been fruitless, as the junta ignores international criticism and refuses to engage with its opponents.

Thailand has instead held unilateral meetings with the junta and deposed democracy leader Aung San Suu Kyi, deepening ASEAN divisions.

A Southeast Asian diplomat told AFP some countries are pushing for the junta to be re-invited to the meetings.

There are also talks about Myanmar deferring the rotating ASEAN chair in 2026, said the diplomat.

"Short of a forceful, direct intervention, there is frankly scarcely anything much which ASEAN could do to help resolve the crisis," said Oh Ei Sun of the Malaysia-based Pacific Research Center.

China's actions in the South China Sea -- which it claims almost in its entirety -- will also feature prominently after Beijing released a new map last week overlapping its own claims with those of several aggrieved ASEAN members.

The map angered countries across the Asia-Pacific region, with protests piling up over the controversial Chinese claims within its so-called nine-dash line, including strong rejections from India, Malaysia, Vietnam and the Philippines.

Leaders will express concern about "land reclamations, activities, serious incidents" in the dispute-rife sea, according to the draft.

This includes actions that have "increased tensions and may undermine peace, security, and stability in the region," it said.

At the East Asia Summit, which will include the United States, China, Japan, India and Russia, Harris is expected to clash with Moscow's wily top diplomat after similar exchanges at recent meetings over the Ukraine war.

In her meetings Harris will "focus on the climate crisis, on maritime security... and on efforts to uphold and strengthen international rules and norms in the region," said National Security Advisor Jake Sullivan.

Xi is expected to skip the G20 summit on September 9-10 in New Delhi.