MANILA - Vice President Leni Robredo must run in the 2022 presidential elections and ensure an opposition victory, her former poll rival and opposition ally former senator Antonio Trillanes IV said Tuesday.

Robredo, for now, would be the opposition's best bet to beat any of President Rodrigo Duterte's anointed candidates, Trillanes told ABS-CBN News.

"We are not entertaining any Plan B," said Trillanes, adding that it was never too early to plan for the elections.

"The opposition is organizing in relation to 2022. We feel it's a must win, not just for the opposition, but for every Filipino," said Trillanes, now a private citizen after his last term in the Senate ended in June.

The staunch Duterte critic added that while Robredo showed a "sweet and gentle way" of opposing the President and his controversial policies, the widow was a force to reckon with.

"I saw her performance in [the] 2016 campaign. I ran against her, magaling ito (she's good), she is a woman of conviction," said Trillanes.

However, Robredo has yet to decide whether she would take on the challenge, Trillanes clarified.

Several politicians had earlier said they would back the President's daughter, Davao City Mayor Sara Duterte-Carpio, should she wish to join the 2022 presidential race.

Analysts said Duterte-Carpio, despite occupying a local post, is an influential figure in national politics as 7 of the 13 candidates endorsed by her regional party Hugpong ng Pagbabago won Senate seats in the recent elections.

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Trillanes said the 2022 polls was not in his agenda, as he could be in jail soon, citing a non-bailable kidnapping case filed against him.

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