Myanmar’s Foreign Ministry has vowed to challenge ASEAN’s unprecedented move to downgrade its participation in the three-day summit, which is being held by video due to coronavirus concerns.
A summit of Southeast Asian leaders has started without a representative of military-ruled Myanmar.
The summit started in Brunei on Tuesday days after the bloc decided not to invite Myanmar junta leader General Min Aung Hlaing for failure to follow a regional peace deal.
Maynmar's ruling military late on Monday said it would only agree to its head of state or ministerial representative attending the summit and refused to send junior representation.
Neither Brunei, the Association of Southeast Asian Nations (ASEAN) chair, nor the bloc's secretary-general made a mention of the no-show in opening remarks at the virtual meeting.
The move was a rare bold step by a regional grouping known for its non-interference and engagement.
In deciding to sideline the Myanmar junta boss, ASEAN cited his failure to make steps to end hostilities, initiate dialogue, allow humanitarian support and grant a special envoy full access in the country.
Myanmar insists the conflict is being stoked by "terrorists" allied with a shadow unity government and says ASEAN is not taking that into account.
Michael Vatikiotis, Asia Director of the Geneva-based Centre for Humanitarian Dialogue, said Myanmar's junta "probably cares about being frozen out of the summit", although it has a history of enduring international isolation.
Since overthrowing Suu Kyi's government, Myanmar's military has killed more than 1,000 people and arrested thousands, monitoring group the Assistance Association for Political Prisoners says.
The junta disputes that count as inflated and says soldiers have been killed in fighting nationwide with armed opposition groups.