MANILA (2nd UPDATE) — Davao City Mayor Sara Duterte-Carpio has resigned from the regional party she founded, just days away from a deadline for national parties to switch their candidates in the 2022 elections.

Duterte-Carpio, 43, "tendered her resignation" as chairperson of Hugpong ng Pagbabago on Thursday morning, said the party's secretary general Anthony Del Rosario.

"It is with profound sadness that I hereby tender my resignation from our beloved party. My support will always be with you and I will always be grateful for all the things you have taught me," read the mayor's letter shared by Hugpong.

The development comes after President Rodrigo Duterte's daughter quit the mayoral race in Davao City, bringing her closer to a potential run for higher office.

The window for Duterte-Carpio to join a national party and register as its substitute candidate closes on Nov. 15, Monday.

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The 43-year-old has come on top in opinion polls throughout this year on preferred candidates for president, but has said she does not want that job.

Duterte-Carpio's ally, lawmaker Joey Salceda, said she would vie for the presidency and that seeking the No. 2 post was not an option.

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Analysts say it is crucial for the Duterte patriarch to have a loyal successor to shield him from possible legal action from his anti-narcotics drive, which is being investigated by the International Criminal Court.

Duterte-Carpio was in Balesin island in Quezon, reportedly attending a birthday party with other political figures, when news broke of her exit from Hugpong.

She later attended a wedding in Cavite, where presidential aspirant Ferdinand "Bongbong" Marcos Jr. was her fellow principal sponsor.

"Nagpapasalamat ako sa mga supporters ko, and I hope na kung ano mang mga mangyari sa mga susunod na mga araw ay maibigay ko sa kanila kung ano gusto nila," Duterte-Carpio said in a chance interview.

(I thank my supporters, and I hope that whatever happens in the next days, I can grant what they want.)

The Philippines holds elections in May 2022 for positions from president down to governors, mayors and local officials.

— With a report from Reuters

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