President Donald Trump’s lengthy trip to Asia has largely ignored human rights issues, despite the United States harboring long-held grievances with how countries in the region have treated their citizens. But aides say he will raise the issue during his meeting Monday with Philippine President Rodrigo Duterte at the summit for the Association of Southeast Asian Nations (ASEAN).

Trump’s meeting here in Manila with Duterte could be a complex dance of flattery and directness, given the fact the Philippine strongman leader has championed an effort that has killed thousands outside of the nation’s judicial system.

Duterte’s controversial “drug war” — which has killed at least 6,000 people, according to police estimates — has drawn international scorn and will likely test Trump’s penchant for diplomatic flattery, providing the US President with one of his most complicated diplomatic encounters of his presidency.

The President, in a series of high-profile speeches and events, has not leveled any public chastisements of human rights leadership in Asia, preferring instead to try to unite countries around his priorities of curbing North Korea and promoting fair trade. Trump did address human rights privately in China, though, Secretary of State Rex Tillerson told reporters.

Trump spoke briefly with Duterte on Sunday night at the opening of the summit, their toast splashed on front pages in Manila on Monday morning as they met again for a brief, but warm, handshake as Trump arrived for his first ASEAN summit. Some 1,500 to 2,000 demonstrators also hit the streets on Monday, speaking out against Trump’s visit, according to a police estimate shared with CNN, many of who appeared to be from the far-left.

The most expansive conversation for the two leaders will happen later on Monday, though, when Trump and Duterte sit down for their first bilateral meeting together. Whether Trump addresses human rights abuses in the country will likely color how that conversation is received by many back in the United States.

Senior administration officials told CNN going into the trip that Trump did plan to address human rights in his meetings with Duterte. But human rights organizations have grown concerned that the President — in part because of his affinity for strongmen leaders — will give Duterte a pass on his crackdown by failing to mention the issue during his multi-day visit.

Human rights concerns

Trump did not mention human rights publicly during his time in China earlier this month, despite the United States’ long-held concerns about the nation’s treatment of dissidents. One of Trump’s only mentions of human rights on his swing through Asia came in a sweeping speech in South Korea, where the President lambasted North Korean leader Kim Jong Un for a range of human rights abuses.

The primary reason for concern among human rights organizations is that Duterte has fully embraced Trump’s style, and Philippine officials, possibly in an attempt to woo the President, have said that the two leaders have a great deal in common.

Philippine presidential spokesman Harry Roque told CNN before the visit that he sees Trump and Duterte as “very much alike in their thinking, their language and demeanor.”

Phelim Kine, deputy director of Human Rights Watch’s Asia division, told CNN that he worries both leaders will look to cement their already burgeoning “bromance.”

“Duterte’s murderous ‘drug war’ will be the elephant in the room, but it’s highly unlikely Trump or any other ASEAN leaders will raise that issue,” Kine said. “Expect both Duterte and Trump to strive to cement what is already a bromance built on a foundation of Trump’s already well-established affinity for ‘strongman’ leaders with well-documented history of abusing the rights of their citizens.”

Kine, whose organization works to track extrajudicial killings in the Philippines, said a failure of the US President to mention human rights would add “insult to grievous injury for the victims and their family members of a 16 month extrajudicial killing campaign.”

Previous praise

Trump has previously praised Duterte’s crackdowns.

“I just wanted to congratulate you because I am hearing of the unbelievable job on the drug problem,” Trump told the Philippine President in their first call earlier this year, according to a leaked transcript obtained by The Washington Post.

Trump did not raise human rights issues in the call. But a senior Trump administration official later tried to walk back Trump’s comment, saying he wasn’t condoning violence and human rights violations but was nodding to the United State’s drug issues.

Even as the drug crackdown has led to sweeping violence and discord in the Philippines, Duterte has embraced his image, including by recently bragging that he has personally killed people.

“When I was a teenager, I was in and out of jail. One fight there, another here,” he said this week in Vietnam ahead of the recent Asia-Pacific Economic Cooperation (APEC) meeting. “At the age of 16, I killed someone.”

A spokesman for the Philippine President said later that he thought the comment “was in jest.”

Leaders in the Philippines view Trump’s visit, though, as a step forward in US-Philippine relations because former President Barack Obama’s relationship with Duterte at the end of his presidency was tense and frayed.

Duterte made slamming Obama a key aspect of his interactions with the United States, including calling the former president a “son of a bitch” and stating that he could “go to hell.”

Days before Trump’s visit, Duterte reportedly even told an audience in Vietnam that Obama was “so black” and “arrogant.”