MANILA – President Rodrigo Duterte on Tuesday expressed gratitude to a Chinese tycoon who helped build a large drug rehabilitation center in the Philippines, saying people like him are the real friends of Filipinos.

In a speech at the inauguration of the mega drug rehabilitation center in Fort Magsaysay in Nueva Ecija, Duterte again lambasted the West for criticizing his controversial war on drugs.

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“When you are a friend, you do not treat him badly before the public. You don’t humiliate an ally, and at all cost you must save the friendship as an ally and friend so that you can help each other in the world of geopolitics,” Duterte said, without directly mentioning the West.

After the US and European Union's criticism of his primary crusade, Duterte has sought to forge closer ties with US’ regional rival China.

Following years of frozen relations due to the bitter South China Sea dispute, ties between the two Asian neighbors turned a new leaf after Duterte became the president.

The president has downplayed the Philippines’ maritime claims and said he wants his government to improve the other aspects of the Philippines’ relations with China.

Duterte recently came home from a state visit to China, carrying billions of dollars worth of investment pledges.

Among the highlights of the resurgence of Philippines-China relations is the building of the huge treatment center by Chinese donors, led by tycoon Huang Rulun.

• READ: Behind Philippines' ties with China, a billionaire and his rehab centers

Duterte said unlike others, Huang “came out of nowhere and came to my office and said he would help me solve the drug problem.”

In his speech, Huang described Duterte as an "irresistible force" fighting drug cartels, whom he said caused "great harm" to the world.

"Drugs wreck the country and bring ruin to the people. It is the common enemy of all mankind," he said.

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