The Armed Forces of the Philippines (AFP) has promised to come up with a recommendation on whether to extend the martial law declaration in Mindanao on or before December 31, Presidential Spokesperson Harry Roque said on Monday.

Roque said AFP has asked last week for 30 days to prepare its recommendation.

"So I think we should hear from the Armed Forces of the Philippines on or before the date of expiration," he said in a press briefing in Davao City.

But Roque, a former party-list congressman, said that AFP may submit its recommendation before Congress goes on holiday break.

Congress will adjourn session on Dec. 16, 2017 until Jan. 14, 2018. The declaration of martial law will expire on Dec. 31 this year.

Under the Constitution, upon the initiative of the President, the Congress may extend the proclamation or suspension of the declaration of martial law for a period to be determined by the Congress, if the invasion or rebellion shall persist and public safety requires it.

But Roque said if Congress is adjourned when the military submits its recommendation, then a special session could be called.

"(C)ongress may have call a special session and cut short its Christmas break… which we did anyway the last time," he said.

President Rodrigo Duterte earlier said the extension of martial law declaration will depend on recommendations of the military and the police.

Duterte placed the entire Mindanao under martial law on May 23 shortly after the Islamic State-inspired terrorists attacked Marawi City. After about five months, the war-torn city was declared free from terrorists. Celerina Monte/DMS