Barack Obama cancels meeting with new Philippine President Duterte

President Barack Obama called off a planned meeting on Tuesday with new Philippine President Rodrigo Duterte, seeking distance from a US ally's leader during a diplomatic tour that's put Obama in close quarters with a cast of contentious world figures.

It's unusual for one president to tell another what to say or not say, and much rarer to call the other a "son of a bitch." Duterte managed to do both just before flying to Laos for a regional summit, warning Obama not to challenge him over extrajudicial killings in the Philippines.

"Clearly, he's a colourful guy," Obama said. "What I've instructed my team to do is talk to their Philippine counterparts to find out is this in fact a time where we can have some constructive, productive conversations."

Early today, National Security Council spokesman Ned Price said the meeting with Duterte was off.

Duterte has been under intense global scrutiny over the more than 2,000 suspected drug dealers and users killed since he took office. Obama had said he planned to raise the issue in his first meeting with Duterte, but the Philippine leader insisted he was only listening to his own country's people.

"You must be respectful," Duterte said of Obama. "Do not just throw questions." Using the Tagalog phrase for "son of a bitch," he said, "Putang ina I will swear at you in that forum." He made the comment to reporters in Manilla. Eager to show he wouldn't yield, Obama said he would "undoubtedly" still bring up human rights and due process concerns "if and when" the two do meet.

The bizarre rift with the leader of a US treaty ally was the most glaring example of how Obama has frequently found himself bound to foreign countries and leaders whose ties to the US are critical even if their values sharply diverge.

In Hangzhou this week, Obama's first stop in Asia, he heaped praise on Chinese President Xi Jinping for hosting the Group of 20 economic summit in his country, an authoritarian state long accused of human rights violations. His next stop was another one-party communist country with a dismal rights record: Laos, where mysterious disappearances have fuelled concerns about a government crackdown.

And sitting down with Turkish President Recep Tayyip Erdogan, Obama made no mention in public of the roughly 35,000 people Erdogan's government detained following the summer's failed coup in Turkey. Instead, he worked to reassure the NATO ally the US would help bring to justice whoever was responsible for plotting the coup.

Obama also spent about 90 minutes yesterday with Russian President Vladimir Putin, another leader whose fate seems intertwined with Obama's in all the wrong ways. On opposing sides of many global issues, the US and Russia are nonetheless trying to broker a deal to address the Syrian civil war and perhaps even partner militarily there.