MANILA, Philippines -- The United Opposition (UNO) warned Malacañang Tuesday against using the escalation of hostilities between government troops and Moro secessionists in the South as an excuse to declare martial law.

"With each passing day, the administration is gaining greater justification to declare martial law, especially if the hostilities escalate and reach areas outside Mindanao," Makati Mayor Jejomar Binay, also president of UNO, said.

In a statement, he said the hostilities would be "very convenient" for alleged plans by the administration to extend President Gloria Macapagal-Arroyo's hold on power beyond the constitutionally mandated end of her term in 2010.

Binay said Arroyo's directive to the military to defend "every inch" of Philippine territory was ironic, considering it was her decision to "cede parts" of Mindanao to the Moro Islamic Liberation Front (MILF) that had rekindled hostilities.

Over the past two weeks, dozens have been killed and thousands displaced as government and MILF forces clashed in North Cotabato and Lanao del Norte after the Supreme Court issued a temporary restraining order against the signing of a memorandum of agreement on ancestral domain (MOA-AD).

The MOA-AD would have paved the way for the creation of the Bangsamoro Juridical Entity, an expansion on the territory of the current Autonomous Region in Muslim Mindanao, which will in effect be a federal state and thus need Constitutional amendment to create.

Earlier, the opposition leader said the administration could be planning a declaration of martial rule to advance its hidden agenda of prolonging Ms Arroyo's stay in power.

"It is hard to believe that the administration has not foreseen the widespread opposition to the terms of the ancestral land accord, and the corresponding MILF retaliation," he said.

"In fact, the events rapidly unfolding in Mindanao present a win-win scenario for Ms Arroyo," Binay said.

He said the public should not let its guard down, especially in the face of possible moves to amend the Constitution by the administration.

"We would be fools to amend our Constitution just to be able to do something that blatantly goes against our self-interest as a nation," Binay said.

"If she cannot govern or manage Mindanao, the solution is not to give it away," he added.