WASHINGTON, April 30 (Xinhua) -- U.S. President Donald Trump on Sunday spoke separately with leaders of Singapore and Thailand to reaffirm the United States' commitment to the Southeastern Asian countries, the White House said.

In a telephone conversation, Trump and Singaporean Prime Minister Lee Hsien Loong hailed the two countries' trade and investment, security cooperation, as well as collaboration on regional and global challenges.

Speaking with Thai Prime Minister Prayut Chan-ocha, Trump affirmed his administration's commitment to playing an "active and leading role" in Asia, in close cooperation with "partners and allies like Thailand," according to the White House.

Trump and Prayut expressed a shared interest in strengthening trade and economic ties.

The businessman-turned-president invited both leaders to visit the White House.

On Saturday, Trump discussed with Philippine President Rodrigo Duterte regional security issues in Southeast Asia, including the threat posed by the Democratic People's Republic of Korea (DPRK).

Duterte's clampdown on drugs was also mentioned during the conversation.

Describing the conversation as "very friendly," the White House said in a statement that the two presidents acknowledged "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."

Trump also invited Duterte to Washington to discuss the bilateral relationship, "which is now heading in a very positive direction," said the statement.

The Obama administration had raised concerns over Manila's extra-judicial killings of drug-trafficking suspects. A meeting between Obama and Duterte was called off last year after Duterte publicly "insulted" Obama.