MANILA -- Vice President Leni Robredo "was just grandstanding" as chief of the government's anti-narcotics drive, an 18-day stint from which she was fired over the weekend, President Rodrigo Duterte's spokesman said Monday.

Robredo failed to seek an audience with Duterte immediately after accepting the post last Nov. 6 and "never presented" plans for tweaking the drug war she had criticized, said Presidential Spokesperson Salvador Panelo.

The Vice President was instead "busy talking" with opposition figures and officials from the US and United Nations, which have both expressed alarm over the deaths of thousands of drug addicts under the Duterte administration, he said.

Robredo was also "taunting and daring the President to fire her," said Panelo.

"She was just grandstanding. She could have just come to Malacañang... She should have gone to the grassroots, she should have gone to the communities, talked with the people there, know their problems," he told ANC.

"She was given an opportunity to assist the program, but she blew it," he said.

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Robredo last week visited one of the poorest and drug-infested areas in the fishing city of Navotas. She also met with reformed drug addicts in Dinalupihan, Bataan.

• Robredo drug war shows why it will take village to solve drug menace

Duterte said he did not trust Robredo and had reservations sharing classified state matters with her, despite appointing her as co-chair of the Inter-Agency Committee on Anti-Illegal Drugs.

Human rights groups accuse the police of systematic executions and cover-ups in its drug war, which the government rejects.

The UN Human Rights Council in July approved a resolution to investigate the Philippines, and the International Criminal Court is conducting a preliminary examination of allegations of crimes against humanity. The government accuses both bodies of bias and interference.

Butch Olano, head of Amnesty International in the Philippines, said Robredo’s bid to stop the bloodshed was never given a chance.

“Vice President Robredo was able to confront the government with the staggering scale of its own crimes. That is why she was sacked,” Olano said in a statement.

Sen. Risa Hontiveros said Duterte was worried about what Robredo might have done.

“Not only they were not ready for her, they were scared,” she said.

Robredo has yet to give a statement on her sacking from ICAD, as of this posting. -- With a report from Reuters