MANILA (UPDATE) - President Rodrigo Duterte's term may be extended if the Philippines shifts from a presidential to a federal form of government, Senate President Aquilino Pimentel III said Wednesday.

Pimentel said if Congress approves a new Constitution in 2019 paving the way for the shift from a unitary to a federal form of government, the succeeding three years would be a transitory period.

During this time, Congress may be open to extend Duterte's term depending on the transitory provisions, he said. Duterte is currently on the second year of his 6-year term set to end in 2022.

"We can extend the president's term one, if really necessary; two, if he is amenable to it; and three, since that extension will be part of the new Constitution, the new Constitution is approved by the people themselves," he said.

Under the federalism proposal of the President's party Partido Demokratiko Pilipino - Lakas ng Bayan (PDP-Laban), a dual executive setup will be applied.

The president will serve as the head of state, chief diplomat, and commander-in-chief. He also has the power to appoint members of the judiciary.

The prime minister will, meanwhile, function as the head of government, dealing with day-to-day affairs such as domestic and economic policy. He also has the function of appointing members of the Cabinet.

Meanwhile, Malacañang on Wednesday reiterated Duterte's earlier statement that he does not intend to extend his term.

"I can categorically state that PRRD (President Rodrigo Roa Duterte) does not want that. He wants to cut short his term rather than lengthen it," Presidential Spokesperson Harry Roque said in a statement.

• Duterte: I do not intend to go beyond my term

Federalism was one of Duterte's main campaign thrusts during the 2016 polls as he believes the current unitary form of government, where power is centralized in the capital, has failed to address the needs of Filipinos and has hampered development outside the seat of power.

House Speaker Pantaleon Alvarez already said he wants to speed up discussions on the proposal to shift to the federal form of government so Congress can convene and create a technical working group to focus on the matter this month.

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