The meeting was seen as a way to repair a historically close relationship

President Donald Trump and Philippine leader Rodrigo Duterte found common ground during their first extended meeting.

The meeting on Monday was seen as a way for the U.S. and the Philippines to repair a historically close relationship that was shaken last year because of Mr. Duterte’s anti-Obama rhetoric.

The leaders discussed trade relations, the Philippines’ large outsourcing industry, U.S. assistance on counterterrorism and their personal relationship, said Harry Roque, a spokesman for Mr. Duterte. He said that they affirmed close ties in a frank 40-minute discussion and that Mr. Trump told Mr. Duterte that he has a friend in the U.S. president.

Before the meeting, Mr. Trump told reporters he and Mr. Duterte “had a great relationship.” Mr. Duterte called his country “an important ally” and shooed away reporters in a joke shared with Mr. Trump, saying, “You guys are the spies.” The night before, Mr. Duterte sang a Philippine love song at the behest of Mr. Trump, according to a video posted on Twitter by a Philippine government official.

#PresidentDuterte sings #Ikaw with #PilitaCorales, upon request of @realDonaldTrump. #Asean2017 pic.twitter.com/VjGCVeOeqG

— Karen Jimeno (@AttyKarenJimeno) November 12, 2017

The tone is a sharp shift from Mr. Duterte’s relationship with the U.S. under President Barack Obama, whom he once insulted.

During their meeting, Mr. Duterte explained his policy in the war on drugs to Mr. Trump, said Mr. Roque. White House press secretary Sarah Huckabee Sanders said “human rights briefly came up,” adding that the conversation—on the sidelines of a meeting of Southeast Asian nations—focused on Islamic State, illegal drugs and trade.

The two leaders also appeared to sidestep the issue of competing territorial claims to the South China Sea, resource-rich waters that are claimed by the Philippines, China and several other nations. China claims almost the entire sea and has militarized some of the disputed islands.

The Philippines won an international arbitration last year that effectively invalidated China’s claims, but Mr. Duterte hasn’t pressed the issue, instead reaching out to Beijing for investment in infrastructure. Mr. Duterte said Sunday the South China Sea is better left “untouched,” for fear of war.

The U.S. doesn’t take sides in the dispute, but has conducted frequent naval patrols in the area.

The issue came up in a meeting between the U.S. and the 10-country Association of Southeast Asian Nations. The countries said they agreed to commit to peaceful resolution of disputes under international law, and to “the rights of freedom of navigation and overflight” and “non-militarization and self-restraint.”

Mr. Trump also met with leaders from other Southeast Asian countries, which included a crossed-arm handshake.

President Trump offered on Sunday, during a visit to another claimant, Vietnam, to act as a mediator. “If I can help mediate or arbitrate, please let me know,” Mr. Trump told Vietnamese President Tran Dai Quang. “I am a very good mediator.”

A Chinese foreign-ministry spokesman on Monday said China is committed to resolving disputes directly with the parties concerned. “We hope the non-regional countries can respect the regional countries’ efforts in maintaining the peace and stability in the South China Sea,” the spokesman said.