President Rodrigo Duterte warned on Thursday he would terminate the Visiting Forces Agreement with the United States after it cancelled the US visa of Senator Ronald dela Rosa.

In a speech in San Isidro, Leyte, Duterte said that Washington should correct this.

"I am warning you, if you don't make the correction, one I will terminate the bases, Visiting Forces Agreement. I will end it, son of a b****," he said.

"I am giving notice and they begin to count. I am giving government and the American government, one month from now, we will talk," Duterte added.

Dela Rosa, who was then Duterte's top cop when he assumed the presidency in 2016, implemented the President's war on drugs until his retirement from the Philippine National Police in 2018. He confirmed on Wednesday that US has canceled his visa.

He has said that he was told that if he wants to apply for another visa, it would be subject to US laws and regulations.

It was not clear why Dela Rosa's visa was canceled.

The US has included in its budget law for this year a provision banning Philippine government officials responsible for the continued detention of opposition Senator Leila de Lima, a staunch critic of the administration, including its war on drugs.

Duterte warned that he would stop other US senators who voted in favor of the ban of Filipino officials from setting foot in America from entering also in the Philippines.

He reiterated that the allegation against De Lima's involvement in the drug trade to collect money for her senatorial bid in 2016 was true.

Duterte said the US senators refused to believe this.

De Lima has since denied the allegation, saying she is a victim of political persecution. Celerina Monte/DMS