The Partido Demokratiko Pilipino-Lakas ng Bayan (PDP-Laban), the political party of Davao City Mayor and presumptive president Rodrigo Duterte, has formed a coalition with the Nacionalista Party, the country's oldest political party.

Duterte witnessed the signing of the coalition for change agreement between PDP-Laban, led by Sen. Koko Pimentel, and the Nacionalista Party, led by former Senator Manny Villar.

Also present during the signing were Villar's wife, Senator Cynthia Villar, and son, Mark; and Davao Del Norte Rep. Pantaleon Alvarez, whom Duterte called as "another Speaker in the offing."

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Among the NP members in the Senate come June 30 are Cynthia Villar, Alan Peter Cayetano, and Antonio Trillanes IV.