MANILA - Former Philippine president Rodrigo Duterte and his two sons plan to run in the country's senate election in 2025, Vice-President Sara Duterte said on Tuesday.

"All of them are raring to run," Sara Duterte, the current Philippine vice-president and daughter of the former president, told reporters less than a week after resigning from the cabinet of President Ferdinand Marcos Jr. and another key post.

There are 12 seats to be contested in the Philippines' upper chamber of congress next year.

Rodrigo Duterte's presidential term ended in 2022. His eldest son, Paolo Duterte, is a congressman, while his other son, Sebastian Duterte, is mayor of the southern Davao city, the bailiwick of the Duterte family.

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Sebastian Duterte is also planning to run for president in 2028, Sara Duterte said.

Sara Duterte's resignation affirmed what political observers had predicted all along that the alliance between their families that brought Marcos and her into power in 2022 was bound to collapse because of their political and policy differences.