MANILA - Senator Antonio Trillanes IV promised Tuesday to present evidence linking President Rodrigo Duterte's son and son-in-law to the narcotics trade when they attend a Senate inquiry later this week.

"Kapag pumunta sila diyan, talagang ibubulaga ko sa kanila yung ebidensya laban sa kanila at magli-link sa kanila sa droga na ito," Trillanes told DZMM.

Presidential son Davao City Vice Mayor Paolo Duterte and his brother-in-law, Atty. Manases Carpio have said they will be attending Thursday's Senate hearing on the P6.4 billion shabu haul that slipped past port inspections last May.

Businessman Mark Taguba, who brokered the 600-kilogram shipment, earlier tagged Duterte and Carpio as members of the alleged "Davao Group," which he allegedly bribed to facilitate corruption at the Bureau of Customs.

Taguba later clarified that Duterte and Carpio's alleged involvement in the corruption controversy was "hearsay in nature."

The vice mayor has also dismissed the allegations as "hearsay". Carpio for his part called Trillanes a "desperate rumor monger."

President Rodrigo Duterte meanwhile said he will resign if any of his children were involved in corruption while Malacañang challenged critics to back their accusations with evidence.

ETHICS COMPLAINT

Trillanes and Senator Richard Gordon had traded barbs over whether to invite the President's relatives to the hearing.

Their heated exchange prompted Gordon to file an ethics complaint against Trillanes, whom he accused of "continuous, unabated, unparliamentary acts, language and conduct."

Trillanes told DZMM he was confident that the complaint would not prosper despite Gordon's claim that he had the support of at least 14 senators.

"I am confident na marami na iyung 3 o 4 na susuporta sa kanya," Trillanes said.

"I will keep on pursuing iyung katotohanan, hindi po ako magpapatinag d'yan [sa reklamo]," he added.