MANILA - (UPDATE) Senator Antonio Trillanes IV on Monday said he will lodge a plunder case against the Tulfo siblings over the P60-million tourism ad placement in their television program.

State auditors flagged the alleged lack of contract when government station PTV aired tourism ads on "Kilos Pronto," a blocktimer hosted by Ben and Erwin Tulfo, when their sister, Wanda Teo was still tourism secretary.

Ben Tulfo last week said he and his brothers will not return the ad fee, contrary to an earlier announcement by Teo's lawyer, Ferdinand Topacio.

• Ben Tulfo won't return P60-M ad payment: 'Mamuti na mga mata niyo!'

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"I intend to file a plunder case against the Tulfo siblings in relation to the 60M DoT ad controversy," Trillanes said in a statement, referring to Ben Tulfo and former Secretary Teo.

"Ginagawa na ngayon ung kaso but siguro within the next few weeks ifa-file na namin 'yan," the senator added.

He also urged the Senate Blue Ribbon Committee to act on his resolution seeking an inquiry into the tourism department's allocation of funds for ads.

Sen ⁦@SonnyTrillanes⁩ plans to file a plunder case against Tulfo siblings on the unreturned P60M advertisement placement in one TV program ⁦@ABSCBNNews⁩ ⁦@ANCALERTS⁩ pic.twitter.com/6MLbpQiCQQ

— sherrie ann torres (@sherieanntorres) July 29, 2018

Trillanes said he has already filed a resolution months back urging the Blue Ribbon Committee to open a probe on the controversial DOT ads but there has been no response.

"Itong Blue Ribbon kasi kung di ka nag-iimbestiga, pinagtatakpan mo. Otherwise i-refer mo sa ibang kumite na willing mag-investigate," he said.

"Kasi una nung ginawa ko ang reso it was supposed to be referred to committee on tourism e inagaw naman nila para dun sa Blue Ribbon pero di naman nag-conduct ng hearing," he added.

The Tulfos have maintained that the ad transaction was above board and that there was no conflict of interest. -- report from Sherrie Ann Torres, ABS-CBN News

• COA cites 'possible conflict of interest' in DOT deal with Tulfo brother