MANILA — The United Nations chief expressed alarm over the plight of Rohingya Muslims in remarks before Myanmar’s Aung San Suu Kyi and other leaders from a Southeast Asian bloc that has refused to criticize her government over the crisis.

UN Secretary-General Antonio Guterres said late Monday that the unfolding humanitarian crisis can cause regional instability and radicalization. He met with leaders from the Association of Southeast Asian Nations on the sidelines of its summit in Manila.

“I cannot hide my deep concern with the dramatic movement of hundreds of thousands of refugees from Myanmar to Bangladesh,” Guterres told the ASEAN leaders. Suu Kyi sat close to him but looked mostly at a wall screen showing the UN leader.

Hundreds of thousands of Rohingya have fled Myanmar’s Rakhine state since late August, when the military launched what they called “clearance operations” in response to insurgent attacks. The refugees say soldiers and Buddhist mobs attacked them and burned their villages to force them to flee.

In its most forceful denial so far, however, Myanmar’s military issued a statement late Monday saying security forces did not commit atrocities during “clearance operations.” It cited an internal investigation that it said had absolved it of any wrongdoing in a crisis that has triggered Asia’s largest refugee exodus in decades.

Gutteres said at the United Nations in September that the attacks against the Rohingya appeared to be “ethnic cleansing.” He said on Friday that it was “an absolutely essential priority” to stop all violence against Rohingya Muslims, allow them to return to their homes and grant them legal status. But his remarks were more measured in front of his ASEAN audience and he did not use the word “Rohingya” itself, a term that angers people in Myanmar who do not consider them a recognized ethnic group.

“It is a worrying escalation in a protracted tragedy and a potential source of instability in the region, and radicalization,” Guterres said, welcoming ASEAN efforts to provide humanitarian aid.

Since the crisis began, Guterres said he has 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.”

Canadian Prime Minister Justin Trudeau also raised the Rohingya issue in a meeting with the ASEAN leaders, including Suu Kyi, in Manila on Tuesday. Trudeau said he has deployed a special envoy to find out how Canada can support the Muslim minorities and pledged to support ASEAN efforts to help resolve the problem.

“This is of tremendous concern to Canada and many, many other countries around the world,” Trudeau said of the Rohingya crisis at a news conference. “Again, we are always looking at not how we can sort of shake our finger and yell at people, but how we can help, how we can move forward in a way that reduces violence, that emphasizes the rule of law, that ensures protection for all citizens.”

The conservative ASEAN, which includes Myanmar and other countries critical of its handling of the Rohingya crisis like Malaysia, has refused to formally discuss the crisis as a bloc in a strongly critical manner. Philippine President Rodrigo Duterte’s spokesman, Harry Roque, however, said at least two leaders raised the issue on Monday during the bloc’s annual summit. — AP