BALI, Indonesia -- Foreign Affairs Secretary Alan Peter Cayetano said Thursday he would seek the leadership of the House of Representatives should he win as representative of Taguig-Pateros in next year's elections.

Cayetano said it was President Rodrigo Duterte who suggested that he aim for the Speaker post to help push forward the administration's legislative agenda.

"I will seek the leadership position in the House but it's a complex matter," Cayetano told reporters here, where Duterte is attending an ASEAN leaders' conference.

"You have to win first sa district mo, and I want to focus on that first, and then you have to win the trust and confidence of the whole Congress," he said.

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If Cayetano becomes Speaker, he will succeed former President Gloria Macapagal Arroyo, who is on her third and last term as Pampanga congresswoman.

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"It's not an easy decision. DFA is a real family, it's a very fulfilling job. To be honest, I thought possibly this is my last job in government so it wasn't easy to decide," Cayetano said.

Cayetano said he had "full confidence" in his successor, whom Duterte has yet to name publicly.