MANILA - The proposed extension of martial law in Mindanao is unconstitutional, Senate Minority Leader Franklin Drilon said Friday.

"We cannot continuously place Mindanao under martial law and suspend the privilege of the writ [of habeas corpus] without an actual rebellion in the region," Drilon said in a statement.

The opposition lawmaker made the comments after the military and police recommended the extension of martial rule in Mindanao beyond its supposed lapse on Dec. 31, citing "significant violent activities" from extremist groups in the south despite the liberation of conflict-stricken Marawi City.

• Military recommends extension of martial law in Mindanao

Drilon said Section 18, Article VII of the Constitution states that martial law may only be extended "if the invasion or rebellion shall persist and public safety requires it."

President Rodrigo Duterte placed the entire Mindanao under martial law on May 23 after the Islamic State-linked Maute terrorist group laid siege on the Islamic city.

• Duterte declares Martial Law in Mindanao

In July, Duterte asked Congress to extend the 60-day proclamation until the end of 2017.

• Congress grants Mindanao martial law extension until December

The government declared the end of hostilities in October, but the Armed Forces of the Philippines (AFP) and the Philippine National Police (PNP) recommended the extension of martial law to President Rodrigo Duterte this week citing persistent security threats in the region.

Other officials had earlier expressed support for extending martial rule in Mindanao to ensure security during the rehabilitation of war-ravaged Marawi.

• Marawi rehab chief seeks martial law extension to secure rebuilding

But for Drilon, the security sector's reason does "not meet the requirements of the Constitution."

"If this is the only reason, the AFP and the PNP can exercise their powers under their respective charters without placing Mindanao under martial law for one whole year," Drilon said.

In a separate statement, Drilon, along with other minority senators, said the proposed extension might hamper rebuilding efforts in Marawi City.

"Martial law, together with the air strikes, was the reason why they fled Marawi in the early days of the Maute siege. Lifting military rule, specifically in Marawi, will hasten the return of affected residents to their homes, according to its citizens," said Drilon and Senators Bam Aquino, Risa Hontiveros, Francis Pangilinan, and Antonio Trillanes IV in a joint statement.

"As security forces reign supreme during martial law, would not military rule actually get in the way of a people-centered rebuilding and rehabilitating of the once vibrant city? What is the need for martial law? Would martial law suspend bidding in the reconstruction of the city?" the joint statement read.

Last week, Presidential Spokesperson Harry Roque brushed aside criticism on the extension proposal from those outside Mindanao.

"What matters most is the view of the stakeholders, the view of the Mindanaoans on martial law. Kung ang mga taga-Mindanao ay hindi tumututol, why should people from Luzon complain? Hindi naman sila apektado," Roque said in a press conference in Zamboanga City.

Defense Secretary Delfin Lorenzana said Duterte is expected to release his decision on the extension of martial law this week.

• Will Duterte extend martial law in Mindanao? Decision out soon []