Former senator Antonio Trillanes IV is highly convinced that an impeachment complaint loomed large over Vice President Sara Duterte, whom he said is already unfit to serve given her recent tirades against the government.

"Perhaps Filipinos can see all the dangers, the red flags, the unfitness of Sara Duterte to hold the position of vice president. And remember, as vice president, she could be president anytime, in cases of emergencies,” Trillanes told reporters at the sidelines of a House quad committee hearing on Wednesday.

“Imagine the behavior she is showing, [would] you give her the power of the presidency?  Filipinos should be terrified. [She's]  not in the right state of mind," he added.

While the looming impeachment complaint is a "joint effort" with Trillanes himself involved, he clarified that it would not be him who would initiate it.

"Let's just wait. I'm not saying I'm the one to file it, I'm saying it will be filed. [The impeachment] is already overripe," the ex-senator told the media.

A visibly enraged Duterte openly announced in a virtual press briefing early Saturday that she had already instructed someone to assassinate President Ferdinand Marcos Jr., First Lady Liza Araneta, and Speaker Martin Romualdez if a supposed plot against her succeeded.

Duterte dropped the bombshell amid what she called the continuing political attacks against her by administration allies, including an ongoing House probe into her use of millions of confidential funds.

Although some House leaders have identified grounds to oust Duterte, including graft, corruption, and betrayal of public trust, they have denied that an impeachment effort is underway.

The power to impeach rests solely with the House of Representatives, but a Filipino citizen could also file an impeachment complaint, which should be endorsed by any member of the lower chamber.

For the complaint to advance to the Senate, at least one-third of House members should vote in favor of it. This is equivalent to 106 members of the current House.

Duterte had previously claimed that she had been aware of the impeachment move and that the House had been plotting it since mid-2023.