Philippine President Rodrigo Duterte will be seated beside United States President Barack Obama and United Nations Secretary—General Ban Ki-moon in a dinner on Wednesday in Laos, two world leaders he has slighted since winning the presidency last May 10.

Duterte will see Obama and Ban today at the Gala Dinner of the Association of Southeast Asian Nations (ASEAN) Summit in Vientiane, Laos, the Palace said.

Duterte made headlines this week after he cursed and attacked the US when asked in a press conference about Obama's plan to discuss with him the human rights situation in the Philippines in light of the government's bloody war on drugs.

Duterte's insulting remarks prompted the White House to cancel what could have been the first meeting between Duterte and Obama on the sidelines of the summit.

Duterte's spokesmen have since said that the president regrets the statements and that the two sides agreed to move the meeting to a later date.

Presidential spokesperson Ernesto Abella said, despite the diplomatic snub, the two are expected to display warmth and civility during the much-awaited encounter.

''In a meeting like this, there are always opportunities for warmth and civility so let us expect that they will have an encounter. And it will be, from the looks of it, civil and warm,'' Abella said in a news conference in Vientiane.

How Duterte would interact with Ban is also being awaited as the foul-mouthed leader once criticized the UN chief for calling him out over the rising cases of extra-judicial killings in the country.

READ: UN chief slams Duterte 'endorsement' of killings

Over 1,300 people have been killed in the Duterte administration's war on drugs, with 60% of the fatalities during police operations, according to monitoring by ABS-CBN Investigative and Research Group.

Duterte had turned down a meeting with Ban on the sidelines of the summit. His office said he could not fit the meeting into his schedule.

The Palace said that on Tuesday, Duterte met with Singapore Prime Minister Lee Hsien Loong, Japan Prime Minister Shinzo Abe and Vietnam Prime Minister Nguyen Tan Dung.