(2nd UPDATE) United States President Barack Obama on Thursday said he did not take Philippine President Rodrigo Duterte's cursing personally.

Duterte's expletive against the US and Obama, which could be translated as "son of a bitch" or "son of a whore," prompted the White House to cancel the bilateral meeting between the two leaders on the sidelines of the Association of Southeast Asian Nations (ASEAN) Summit in Laos.

Duterte issued the scathing statements in reaction to Obama's reported plan to bring up the human rights situation in the Philippines in relation to the new administration's controversial war on drugs.

But in a news conference on Thursday, Obama downplayed the incident and said the two countries must continue their cooperation.

''I did shake hands with President Duterte last night. It was not a long interaction, and what I indicated to him is that my team should be meeting with his and determine how we can move forward on a whole range of issues,'' Obama said.

Obama added, Duterte's cursing is not really directed at the person. He noted how Duterte once uttered expletives against the Pope.

''As I said, when I was asked about this in China, I don't take these comments personally because it seems as if a phrase he's used repeatedly, including directed to the Pope and others. And so I think it seems to be just a habit, a way of speaking for him,'' he said.

Duterte's statement raised concerns that the relations between traditional allies Manila and Washington could suffer under the leadership of the firebrand Philippine leader.

Manila and Washington have since downplayed the diplomatic gaffe, saying the relations between the two countries remain strong.

''It has no impact on our broader relationship with the Philippine people and the wide range of programs and security cooperation we have with this treaty ally, and it certainly has no impact in terms of how we interpret our obligations,'' Obama said.

Duterte's aides have also said that the president regrets the statements, and that the two sides had agreed to move the bilateral meeting at a later date.

DO WAR ON DRUGS 'THE RIGHT WAY'

While noting how the relations between Manila and Washington should not be affected, Obama said the US would not back down on its position against waging a war on drugs that is not consistent with the rule of law and respect for human rights.

''As I said in China, we want to partner with the Philippines on this particular issue of 'narco-traffickers', which is a serious problem in the Philippines. It's a serious problem in United States and around the world,'' he said.

''On that narrow issue, we do want to make sure that the partnership we have is consistent with international norms and rule of law. So we're not going to back off our position that if we're working with a country, whether it's on anti-terrorism, whether it's on going after drug traffickers, as despicable as these networks may be, as much as damage as they do, it is important from our perspective to make sure that we do it the right way."

Obama warned that employing unlawful means in waging a war against illegal drugs may spawn more problems.

''Because the consequences when you do it the wrong way, innocent people get hurt. And you have a whole bunch of unintended consequences that don't solve the problem."

Over 1,400 have been killed either by police or suspected vigilante groups since Duterte won the presidential elections last May 9. Sixty percent were killed during police operations, based on monitoring by the ABS-CBN Investigative and Research Group.

A total of 450 deaths (32%) were killed by unidentified assailants.

Philippine National Police (PNP) Chief Ronald dela Rosa believes those killed by unidentified assailants were likely carried out drug syndicates themselves.

Obama, meanwhile, said he hopes that Duterte and his team ''get acclimated'' to the presidency.

''My hope and expectation is that as President Duterte and his team get acclimated to his new position, they're able to define, clarify what exactly they want to get done,'' Obama said.

''Hopefully, it will be on a strong footing by the time the next administration comes in."