Wanda Tulfo-Teo, a small tourist operator from the president’s southern hometown of Davao City prior to her current role, was engulfed in controversy after a department advertisement worth 60 million pesos (RM4.6 million) ended up on her brother’s television show for a state-run network.

Confirming the resignation, Duterte’s spokesman, Harry Roque, said, “I think Secretary Teo, being a close associate of the president, did what she thought was the best course of action, and we thank her.”

Roque said the resignation was not an admission of guilt as the president’s office would leave the country’s ombudsman to determine the public officials liable for any wrongdoing.

There was no announcement on a replacement for Teo.

Teo handed in her resignation before a cabinet meeting on Monday night, her spokesman, Ferdinand Topacio, told a news conference, contradicting media reports that she had been fired.

A report by the state-run Commission on Audit showed the tourism department had placed about 60 million pesos (RM4.6 million) worth of advertisements on PTV4 that ended up in Teo’s brother’s programme, related to crime and public service.

“She did not know that the 60-million-peso (RM4.6 million) ad spend was placed for her brother’s show,” Topacio added. “We will prove that she is devoid of any wrongdoing in the proper forum.”

Duterte, who has vowed not to tolerate even a “whiff of corruption”, has removed dozens of bureaucrats over graft allegations.