MANILA (UPDATED) - President Rodrigo Duterte has signed an Executive Order creating a team that will study proposals to amend the 1987 Constitution, Executive Secretary Salvador Medialdea said Thursday.

"The President has issued the other day an executive order creating the committee for consultative study of the Constitution," he said.

Medialdea also told the Senate Committee on Constitutional Amendments, led by its Chair Senator Franklin Drilon, that the body shall be composed of 25 selected individuals.

He said President Rodrigo Duterte's preferred mode of changing the Constitution is through constituent assembly (Con-ass), citing cost efficiency.

Duterte originally preferred to review the 1987 Constitution through a constitutional convention, whose delegates are chosen through election, but House Speaker Pantaleon Alvarez said in a previous interview that Duterte eventually favored Con-ass after learning that a constitutional convention would cost P7 billion.

Some critics, however, said having a Con-ass revise the Constitution will open it to suspicion that sitting solons will write their vested interests into the Charter.

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Alvarez said he cannot blame the public for putting too little trust in Congress, but having a Constitutional Commission (Con-Com) similar to what had been indicated in Duterte's EO may dispel fears that sitting lawmakers will advance their self-interests in drafting the new Constitution.

Former Senator Nene Pimentel meanwhile told the Senate that if Con-Ass will be the mode of changing the Constitution, the Senate and the House of Representatives should vote separately so as not to dilute the vote of the senators.

Drilon said there will also be hearings in Baguio City, Cebu City and Cagayan De Oro City.