MANILA– Myanmar faced mounting international pressure Tuesday to facilitate the immediate return of hundreds of thousands of Rohingya who fled to Bangladesh.

Antonio Guterres, the secretary general of the United Nations, met with de facto Myanmar leader Aung San Suu Kyi, who is also state counselor and foreign minister on the sidelines of the 31st ASEAN summit in the Philippine capital to discuss the situation in Rakhine state, which led to thousands of Rohingya Muslims seeking shelter in neighboring Bangladesh amid an outbreak of violence since late August.

The Secretary General highlighted that strengthened efforts to ensure humanitarian access, safe, dignified, voluntary and sustained returns, as well as true reconciliation between communities, would be essential, the U.N. said in a statement Tuesday.

He also stressed the importance of implementing the Rakhine Advisory Commission recommendations.

The Rakhine Advisory Commission, appointed by Myanmar’s government and led by former U.N. Secretary-General Kofi Annan, released a final report on Aug. 24, in which it listed recommendations for resolving tensions in Rakhine. Among other measures, the commission called for reviews of Myanmar’s Citizenship Law and ending other restrictions on Rohingya Muslims, a stateless minority concentrated in the state.

In a speech before his meeting with the Association of Southeast Asian Nations (ASEAN) on Monday night, Guterres said he could not hide his deep concern with the dramatic movement of hundreds of thousands of Rohingya refugees, who often undertake a perilous crossing into Bangladesh.

It is a worrying escalation in a protracted tragedy and a potential source of instability in the region, and radicalization, Guterres said.

The United Nations welcomes constructive approaches by ASEAN, including the provision of humanitarian aid to northern Rakhine. Since the beginning of the crisis, and beyond the end of violence, I have called for unhindered humanitarian access to affected communities; and the right to safe, voluntary and dignified return of those who fled, to their places of origin.

Malaysian Prime Minister Najib Razak, who was among foreign leaders attending the ASEAN Summit and side meetings in Manila, echoed the secretary-general’s concerns that Rohingya could become radicalized if they were kept repressed.

On the issue of the Rohingya refugees and the state of Rakhine, I asserted that, as an organization, we can’t keep silent as the world is waiting for ASEAN’s response on this crisis, the Malaysian leader wrote in a post on his blog.

ASEAN needed to deal with the crisis, which affected his country where Rohingya had fled to in the past, because these refugees are potential targets to be influenced by IS or DAESH, Najib warned, using an Arabic name for the extremist group Islamic State.

When I raised the issue of Rohingya, Aung San Suu Kyi, in her response, said the Government of Myanmar was negotiating an MoU with the government of Bangladesh to determine the return of refugees to the state of Rakhine. This MoU will be signed soon, he added.

U.S. President Donald Trump, who met Monday with his Philippine counterpart, Rodrigo Duterte, said both leaders discussed the Myanmar crisis and called for an expeditious delivery of humanitarian assistance to affected communities.

Trump and Duterte also welcomed the Myanmar government’s commitment to end the violence, restore media access, ensure the safe return of displaced persons.

Trump and Guterres were among world leaders who converged on the Philippine capital to attend the annual summit of leaders of ASEAN leaders, a regional bloc whose members have a longstanding collective policy of not interfering in one another’s internal affairs

The latest exodus of Rohingya into southeastern Bangladesh was driven by a military crackdown in Rakhine. It followed attacks on police and army posts there on Aug. 25 that were blamed on Arakan Rohingya Salvation Army (ARSA) insurgents. About a million Rohingya refugees, including those who fled earlier cycles of violence in Rakhine, are now sheltering in Bangladesh.

On Monday, the Tatmadaw (Burmese military) released findings by a team that investigated the August attacks. Their report concluded that the violence was initiated by ARSA Bengali terrorists who attacked some 30 police outposts.

The main conclusion of the report, in which more than 3,200 villagers and 804 witnesses were interviewed, was that the security forces were only fighting against ARSA Bengali terrorists.

They never shot at the innocent civilians, the report said, contradicting scores of testimonies from Rohingya refugees who told rights workers in Bangladesh that they had fled because Buddhist mobs had launched widespread violence, including acts of arson, murder and rape.

The report also claimed that Bengali terrorists were originally estimated at about 4,000, but that when they launched their attack, their numbers had grown to about 10,000.

The fighters, whom the report never classified as ethnic Rohingya, but as Bengali terrorists, allegedly used home-made bombs and locally made mines set off by remote control. Police, on the other hand, just used small arms, the report said.

As such, the security forces aided by laws related to the wars in conducting area clearance operations. So, it is found that those security forces did not perform the use of excessive force, it said, adding that there was no death of innocent people.

Canadian Prime Minister Justin Trudeau, who was also in Manila, said he had brought up the situation in Rakhine with Aung San Suu Kyi.

This is of tremendous concern to Canada and many, many other countries around the world, Trudeau told reporters. And, again, we are always looking at how we can sort of shake fingers and yell at people, but how we can help move forward in a way that reduces violence, that emphasizes the rule of law and ensures protection for all citizens.

But while world leaders were vocal about the crisis, the troubles in Rakhine were not mentioned in an official statement from ASEAN’s chairman that is traditionally issued as the outcome document at the end of the summit.