MANILA (UPDATE) - Following his unanimous decision loss to Yordenis Ugas, Senator Manny Pacquiao now faces another challenge: a disloyalty complaint for alleged violation of the PDP-Laban constitution that could see him expelled from the party.

PDP-Laban Secretary-General Melvin Matibag earlier said Pacquiao's camp has 10 to 15 days to explain why they should not be expelled from the party after the boxing-senator's alleged conversion of regional party People's Champ Movement (PCM) into a national one.

• Cusi faction: Pacquiao faces expulsion from PDP-Laban
• Rival PDP-Laban faction accuses Pacquiao of breaking party rules

"May due process kami sa partido (The party has a due process) and because of that, I believe there is a complaint against him regarding that allegation. We will have to run him through the process of the party and that means he will be given a chance to explain," the party's executive vice president, Cabinet Secretary Karlo Nograles, told ANC's Headstart.

"We’ll allow him to answer allegations. There will be a hearing, there will be a decision about it. May grievance procedure kami (We have a grievance procedure) when it comes to party members."

The rift within the ruling party began when the senator was selected as party president in December without the knowledge of its chairman President Rodrigo Duterte, said Energy Secretary Alfonso Cusi, who leads the faction against Pacquiao.

Pacquiao then refused to attend an executive council meeting where party members urged Duterte to run for vice president next year.

The two factions separately filed documents required for political parties in the upcoming 2022 national elections before the Commission on Elections.

• 2 party filings: Pacquiao-Cusi feud over control of PDP-Laban enters Comelec

GO-DUTERTE TANDEM

The executive committee will push through with its plan to nominate Senator Christopher "Bong" Go as its presidential nominee and Duterte as its vice presidential nominee in next year's polls, Nograles said.

The party's national convention is on September 8, he added.

• Go-Duterte tandem 'logical and popular' choice for PDP-Laban, official says

"That’s a nomination that will have to run through the body," he said.

"It will depend on our nominee. They are free to accept the nomination or not," he added.

The party is "not discussing substitution," according to Nograles.

PDP-Laban in the 2016 national elections selected Duterte to run for president as the substitute of Martin Diño who withdrew his candidacy. Diño serves as an undersecretary of the Department of Interior and Local Government.

• Party picks Duterte as substitute in presidential race

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