MANILA (UPDATE) -- President Rodrigo Duterte's former foreign secretary and running mate, Taguig Rep. Alan Peter Cayetano, was elected speaker on Monday, handing him a strategic ally in the House with some of his campaign promises still pending.

Cayetano will serve as speaker for 15 months under a power-sharing agreement that Duterte brokered. Marinduque Rep. Lord Allan Velasco will serve the remaining 21 months of the 18th Congress.

The President's eldest son, Davao City 1st District Rep. Paolo Duterte, nominated Cayetano despite his earlier opposition to the term-sharing deal.

Velasco and another contender for the speakership, Leyte Rep. Martin Romualdez, also nominated Cayetano. Romualdez had agreed to drop out of the race, settling for Majority Leader.

Romualdez is a long-time ally of former Speaker Gloria Macapagal Arroyo and a relative of former first lady Imelda Marcos whose family supported Duterte.

The President also said he would back Romualdez's possible vice presidential bid in 2022.

Iloilo Rep. Janet Garin, a former health secretary, and AKO Bicol Rep. Alfredo Garbin Jr. both nominated Manila Rep. Benny Abante. With only 2 candidates for speaker, the non-winner was expected to become minority leader.

Abante and Cayetano voted for each other in a show of statesmanship. Cayetano also got the votes of Davao del Norte Rep. Pantaleon Alvarez, who had also eyed the speakership this term, and Pampanga Rep. Mikey Arroyo.

Cayetano had been critical of Arroyo’s parents during the presidency of the latter's mother Gloria Macapagal-Arroyo, who was House speaker in the last session.

In 2006, then First Gentleman Mike Arroyo filed an ethics case and a separate libel case against Cayetano after the Taguig-Pateros lawmaker alleged Mike Arroyo had secret bank accounts overseas. Mikey and his late uncle Iggy, then a lawmaker himself, were signatories to the ethics complaint.

Before taking his oath as speaker, Cayetano received prayers from his colleagues led by CIBAC Rep. Eddie Villanueva, an evangelist.

In his speech, Cayetano thanked his colleagues for the trust.

"Sana po ako'y maging worthy at sana po ay tulungan niyo ako para sa loob ng 15 na buwan ay mapagsilbihan po natin ang ating mga kababayang mabuti at lahat po ng nasa legislative agenda, ubusin na natin at ipasa na natin dahil mas magandang magawa na natin ito kaagad," he said.

(I hope I will be worthy and I hope that you help me so that in 15 months I will be able to serve our people well, and everything in the legislative agenda we will finish and pass because it's better that we do this fast.)

Lawmaker Duterte, meanwhile, said members of the Davao coalition in the House "respect the decision of the President" and hopes the term-sharing agreement will hold.

"...[P]ero sinabi ko nga 'yung term-sharing nila is an agreement between them and the President so right now, tutal sabi naman ng Presidente si Congressman Alan ang mauna eh, after 15 months and he decides to run [or] to resign, eh siyempre hindi naman puwedeng hindi tayo mage-election so from there doon na lang magde-decide ang Davao coalition," the younger Duterte said.

(But I said the term-sharing is an agreement between them and the President so right now, besides, the President said Congressman Alan will be first, after 15 months and he decides to run or to resign, eh of course we have to have elections, so from there, that's when the Davao coalition will decide.)

Apart from Duterte, below are other deputy speakers elected during Monday's inaugural House session:

• South Cotabato Rep. Ferdinand Hernandez
• Sorsogon Rep. Evelina Escudero
• Antique Rep. Loren Legarda
• ABONO partylist Rep. Conrad Estrella III
• Surigao del Sur Rep. Prospero Pichay
• Antipolo City Rep. Roberto Puno
• CIBAC partylist Rep. Eddie Villanueva
• Pampanga Rep. Aurelio Gonzales
• Surigao del Sur Rep. Johnny Pimentel
• Camarines Sur Rep. LRray Villafuerte

Other officials named were:

• Rep. Jesus Crispin Remulla, Senior Deputy Majority Leader
• Rep. Isidro Ungab, House Appropriations Committee
• Rep. Bambol Tolentino, House Accounts Committee

The new leaders of the House of Representatives and the Senate were elected ahead of Duterte's fourth State of the Nation Address late Monday, where he is expected to discuss his plans for the remainder of his term.

The President has yet to fully deliver on his promises to overhaul the tax system and shift the country's form of government to federalism, a move aimed at spreading wealth and political power to the countryside from the capital, Manila.

• Duterte endorses Cayetano-Velasco term-sharing in House Speakership
• Cayetano: Term-sharing pact with Velasco to be observed

BIG BOOST

Cayetano is a "big boost" when it comes to pushing for the President's agenda in Congress, Institute For Political and Electoral Reform Executive Director Ramon Casiple told ABS-CBN News.

"He is close to the President, he has knowledge on both houses, kabisado niya ang thinking ng Cabinet kaya malaki ang matutulong niya sa agenda ni President," he said.

(He is close to the President, he has knowledge on both houses, and he knows how the Cabinet thinks that's why he can greatly help the agenda of the President.)

Cayetano, who was first elected as Taguig representative in 1998, served as senator for a decade before his Cabinet appointment and vice presidential bid in 2016.

His membership in the Nacionalista Party, the third biggest bloc in the House, can also help swing votes in the chamber, Casiple said.

WIN-WIN SOLUTION

Duterte brokered the term sharing deal to accommodate Velasco, his party mate in PDP-Laban, said Casiple. The President's party is the biggest bloc in the House with 86 members.

"Velasco is not weak but baguhan siya. Wala siyang klaseng influence o connection sa Cabinet, kahit sa Kongreso wala siyang ganung klase ng clout," he said.

(Velasco is not weak but he is a newcomer. He does not have the same influence and connection to the Cabinet, even in Congress he does not have the same clout.)

-- With reports from RG Cruz, ABS-CBN News