President Rodrigo Duterte denied that he apologized to Vice President Leni Robredo for believing fake news that she invited United Nations officials to look into the administration’s controversial war on drugs as co-chair of the Inter-Agency Council on Anti-Illegal Drugs.

• Duterte 'sorry' to Robredo for believing 'fake news' that she invited UN probers

"I was talking to him earlier precisely because of that, and he denied that he has apologized," Presidential spokesman Salvador Panelo told reporters during a hastily-called briefing in Busan, South Korea.

President Duterte issued a rare apology on Saturday after realizing that reports saying Robredo invited UN probers to the country was false.

"If she says that’s false news, ako I believe her. And I am sorry because I said you only realize that it is false news when the news comes out. And you hear it and you talk about it, you react to it, that is the problem,” Duterte told reporters in Davao.

• Robredo warns Duterte vs 'fake news' that she invited UN prosecutor

Panelo however clarified that the Chief Executive was only sorry for basing his assumptions on a false information.

"In other words he is just saying that he is sorry that he relied on false news," he said.

Reports that he apologized to Robredo apparently irked Duterte, who immediately announced that he is firing her from her post as ICAD co-chair.

"I am firing her right now...sabi niya hindi apology 'yan. Sorry lang kung false news 'yan," Panelo quoted Duterte as saying.

Malacanang meanwhile continued to criticize Robredo for talking to officials from the United States embassy and the United Nations whom they accused of remaining “out-of-touch from the realities of the local drug problem on the ground.”