Watch more in iWantv or TFC.tv

MANILA - President Rodrigo Duterte himself put the "nail in the coffin" on the charges filed against him before the International Criminal Court with his extrajudicial killing "admission," a former party-list lawmaker said Monday.

Lawyer Neri Colmenares, who represents kin of drug war fatalities in an ICC case against Duterte, said they will include the President's "extrajudicial killing sin" remark in a supplemental pleading to be filed before the Netherlands-based tribunal.

• Duterte: 'EJKs' my only sin

"This new admission by the President practically, at least for me, puts a nail in the coffin on the case of Duterte before the ICC," he told ANC, citing a Supreme Court ruling that say "admission against interest is presumed to be true."

Presidential Spokesperson Harry Roque has defended Duterte, saying the chief executive's remark was not an admission of guilt but was just to emphasize he has not been accused of corruption despite accusations of being behind the killings.

• Palace: Duterte 'not serious' about statement on EJKs

Colmenares said the President's camp can use that in their defense before the ICC.

The lawyer said he is confident that the ICC will rule in their favor especially after they submitted pieces of evidence that led to the conviction of Duterte before the International People's Tribunal, which he said will prove his guilt on killings under the drug war.

• International People's Tribunal convicts Duterte of human rights abuses

"They have all this evidence about 'Red October' but they don't have intelligence reports on who are committing these thousands and thousands of crime? What kind of intelligence do you have? The most palpak (fail) intelligence in the world," he pointed out.

• Palace: ICC to start ‘preliminary examination’ into 'crimes against humanity' charges vs Duterte