Malacanang said on Thursday martial law extension in Mindanao has "legal and factual bases".

In a statement, Presidential Spokesperson Harry Roque said the legislative and executive departments have decided further extension of martial law in Mindanao is necessary to quell the remaining terrorists who brought destruction to Marawi and its neighboring communities.

"The legal and factual bases of the martial law extension have been clearly established based on the security assessment by our ground commanders," he said.

In a vote of 240-27, Roque noted the overwhelming approval by Congress to further extend the proclamation of martial law.

Roque said the executive is ready to defend the martial law extension from Jan. 1 to Dec. 31, 2018.

"We are thus prepared to defend our position before the High Court," he said.

Roque also debunked the petitioners’ allegations that martial law may lead to “extension in perpetuity."

"(T)hese are mere surmises and conjectures and not supported by law and the Constitution. Martial law in perpetuity is a scenario that neither the President, Congress or the Supreme Court will allow as it is patently unconstitutional," he stressed.

Opposition congressmen, led by Albay Rep. Edcel Lagman, have filed on Wednesday a petition questioning the constitutionality of martial law extension.

The petitioners have said that martial law extension was not needed anymore because there is no longer rebellion in Marawi City, which was liberated from the Islamic State-linked Maute terrorists in October.

“The extension of martial law and the suspension of the privilege of the writ of habeas corpus against remnants of terrorists groups is akin to killing a fly with a sledgehammer,” the petition said.

The petitioners also sked the Supreme Court to issue a temporary restraining order (TRO) or a writ of preliminary injunction to stop the implementation of the martial law extension. Celerina Monte/DMS