MANILA - In a sign of improving ties between Manila and Washington, US President Donald Trump invited Philippine President Rodrigo Duterte to his office during a phone call late Saturday, the White House said Sunday.

Trump invited Duterte to the White House "to discuss the importance of the United States-Philippines alliance, which is now heading in a very positive direction," the US Office of the Press Secretary said in a statement.

The White House gave no details of when the leaders would meet in Washington, but said Trump looked forward to visiting the Philippines in November as part of two summits with other Asian nations.

Trump and Duterte talked over the phone after the Filipino leader hosted other Southeast Asian leaders in the 30th ASEAN Summit.

Before Trump took office, Duterte had hurled tirades against Washington for criticizing the deaths of thousands of drug suspects in his war on illicit drugs.

Ties between security allies US and Manila improved under Trump, who has not openly criticized Duterte's controversial campaign so far.

The US State Department however recently described the drug-related killings in the Philippines as "troubling."

In its statement, the White House said the two leaders touched on the issue during their conversation.

Trump and Duterte "discussed the fact that the Philippine government is fighting very hard to rid its country of drugs, a scourge that affects many countries throughout the world," the White House said.

Malacañang meanwhile said Trump expressed "understanding and appreciation" of the challenges faced by Duterte, especially on the matter of dangerous drugs.

The White House and Malcañang both added that the two leaders discussed the concerns of Southeast Asian Nations regarding regional security, including the threat posed by North Korea.

Duterte earlier said he would urge Trump to show restraint on North Korea after its latest missile test rattled allies Japan and South Korea.

Saturday's conversation between Duterte and Trump was the second time they talked over the phone. Last December, the Philippine President called Trump to congratulate the latter over his election victory. -- With Reuters

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