President Rodrigo Duterte said Chinese billionaire Huang Rulun did not ask for any favor when he extended a multi-billion fund for the construction of two huge rehabilitation centers for drug dependents in the country.

Duterte told reporters Thursday night Huang just wanted to help.

"I would not comment on the domestic affairs of China, especially one who has been kind to us. He did not ask for anything. He just wanted to be of service to his fellowmen," Duterte said.

China has been investigating Huang over corruption allegations as his company was allegedly involved in bribery, news reports said.

"He's (Huang) a multi-billionaire. He has 20 hotels," Duterte said.

"I would not venture any statement because people might not like it actually," he said, adding he thanks Huang for his help.

Chinese Ambassador Zhao Jianhua said Huang, who donated $1.4 billion for the construction of two huge drug rehabilitation centers in the Philippines, used his own money to fund the facilities.

“The information I got is that this is not a corrupt money,” Zhao told journalists at a Chinese embassy reception Thursday evening.

Zhao said Huang deserves credit for helping the administration of Duterte fight the drug menace.

“He did donate a big amount of money for his effort to help the Filipino people to fight against drug problems, to deal with drug problems. I think he deserves some merit because of that,” Zhao said.

Huang was relieved from his post in an advisory council in Fujian province last week, according to reports, as a government anti-corruption agency in Beijing announced he is facing probe over bribery allegations.

Zhao said Huang’s contribution to the Philippine government’s anti-drug campaign and his possible involvement in corruption cases should be treated as “two different matters.”

“They’re entirely different,” the envoy noted. “The money he contributed has nothing to do with corruption cases.”

The mega-rehabilitation center, which could accommodate up to 10,000 patients located in Fort Magsaysay, Palayan City, was one of the centers that Huang funded. Celerina Monte/DMS