MANILA - "Don’t come to the Philippines when uninvited."

Presidential Spokesperson Harry Roque Jr. had this to say to Agnes Callamard, United Nations' special rapporteur on extrajudicial, summary or arbitrary executions, as the administration stepped up its rhetoric against the official, following a rebuke from the Office of the United Nations High Commissioner for Human Rights.

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Callamard in May visited the Philippines to attend a drug policy forum co-sponsored by the Commission and Human Rights (CHR) and the Free Legal Assistance Group (FLAG), a human rights group.

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At the time, Callamard was criticized for paying a visit to the Philippines, but she noted that she was not here to assess the country's human rights situation, adding she informed the government of her arrival.

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Presidential Spokesperson Harry Roque Jr., however, still took offense of Callamard's visit, saying it was "an act of bad faith."

"The President has expressed his greatest displeasure at the conduct of Agnes Callamard who came to the Philippines uninvited despite the fact that at that time we were already negotiating the requisite invitation required for special rapporteurs to be able to investigate in member nations of the United Nations," Roque said in a news conference in Malacañang Thursday.

"So what she did to come here despite the fact that negotiation was still pending was an act of bad faith and of course what angered the President in particular is on her visit here, she brought a resource person who the President believes stated that prohibited drugs is not harmful to human health."

Duterte drew a sharp rebuke from Office of the United Nations High Commissioner for Human Rights' spokesperson Rupert Colville after the Chief Executive threatened to slap the special rapporteur.

Roque, in turn, told Colville that Duterte "should be taken seriously but not literally."

The Duterte government has a standing invitation for Callamard to visit the Philippines and conduct a probe into the human rights situation here, but the special rapporteur rejected this as it comes with conditions, such as holding a public debate with the President.