The Association of South-East Asian Nations ASEAN says it is deeply disappointed by the limited progress made by Myanmar's military rulers in implementing a peace agreement to end the conflict in the country.
The statement was made by the 10 nation bloc's foreign ministers, as the ASEAN chair Cambodia hosts a broader international gathering, including counterparts from the United States, China, Russia, Japan, Britain and Australia.
The US House of Representatives Speaker Nancy Pelosi's solidarity trip to the self-ruled island this week has infuriated Beijing, as the gathering has been overshadowed by tensions surrounding Taiwan.
The Chinese Foreign Minister Wang Yi and Russian Foreign Minister Sergei Lavrov walked out of a plenary meeting on Friday when their Japanese counterpart spoke, a person in the room said.
On Thursday, Mr Wang cancelled a meeting with Japan's Yoshimasa Hayashi in Cambodia, with China claiming displeasure over a G 7 statement urging it to resolve Taiwan's tension peacefully.
ASEAN warned on Thursday of the risks of miscalculations in the Taiwan Strait and serious confrontation between major powers, though the final communique did not mention the situation.
The communique recommended that an ASEAN summit in November evaluate progress by the junta in implementing a peace plan to guide the decision on the next steps, and its generals, who have defended the recent executions as necessary, are not allowed to attend its meetings until progress in the ASEAN peace plan is demonstrated, because of the crisis Myanmar has faced since last year's coup.
The five-point peace consensus calls for an end to violence and asks for all parties to engage in dialogue and for ASEAN to provide humanitarian assistance.
There has been little sign of the end of the violence in Myanmar, with conflict spreading in towns and cities after the army crushed mostly peaceful protests.
The Cambodian Prime Minister Hun Sen said at the beginning of the meeting that ASEAN would have to reconsider the peace plan if Myanmar's military rulers executed more prisoners.
A senior US State Department official said this week that the United States was looking at what can be done to sustain and increase pressure on the Myanmar generals.
Some members of the ASEAN — which have a tradition of non-interference in member countries' internal affairs — have been strident in their criticism of Myanmar.
The junta had been frustrated with members of the ASEAN and making a mockery of the peace agreement, which should be inclusive of its opponents, according to Malaysian Foreign Minister Saifuddin Abdullah.
On Friday, the ASEAN ministers were joined for the plenary sessions of the East Asia Summit and the annual ASEAN Regional Forum security gathering, attended by 27 foreign ministers.
I have to say that never before, not like this year, we have been confronted with so many dangers at the same time," said Prak Sokhonn, Cambodian Foreign Minister.
It was reported that despite the tensions over Taiwan, China's Mr Wang arrived for ASEAN's gala dinner late on Thursday, and walked out of the venue moments after, according to Reuters journalists.
Mr Wang and US Secretary of State Antony Blinken have refused to meet each other in Phnom Penh.
Mr Blinken told a plenary meeting on Friday that China's reaction to Ms Pelosi's visit to Taiwan was flagrantly provocative, a western official said.