MANILA - President Rodrigo Duterte's planned shift to federalism may not prosper in the 18th Congress as the public is okay with the current system of government, Sen. Cynthia Villar said Saturday.

People are more concerned about changing economic provisions in the constitution, not changing the form of government, Villar told reporters 2 days before Duterte delivers his 4th State of the Nation Address on Monday, when the new session of Congress begins.

"May big resistance sa charter change so mahirap 'yan na mapasa," she said, noting that several charter change proposals were filed but were thumbed down by previous Congressional leaders.

(There is a big resistance to charter change so it would be difficult to pass.)

"Para kasi ang mga tao kung ito ang system at OK naman sila, natatakot sila na mag-risk in another system na hindi nila alam kung ano ang nangyayari," she said.

(It seems that if this is the system and people are OK with it, they're afraid to risk trying a new scheme where there are uncertainties.)

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Decentralizing power from the capital and empowering regional governments were among Duterte's campaign platforms when he ran for president in 2016.

A draft federal charter was crafted by a consultative committee formed by the executive branch, but this eventually languished in the legislature.

"Federalism is something very difficult to comprehend kasi maraming model ng (because there are many models of) federalism and they have not pointed what model of federalism they are going to do," said Villar, an administration ally who topped the May senatorial polls.

"Mahirap kasi okay naman tayo ngayon. Hindi natin alam what will be our lives in federalism," she said.

(It's difficult because the system we have now is okay. We don't know what will happen to our lives under federalism.)

Changing provisions on retail trade would be more palatable to the public, said Villar, whose husband former senator Manny Villar is the country's richest businessman.

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- report from Anjo Bagaoisan, ABS-CBN News