President Rodrigo Duterte may issue another proclamation if Congress would not extend the 60-day martial law period if rebellion and invasion persist in Marawi City.

"If Congress does not extend on the 60th day upon initiative of the President then there can be no extension. Another proclamation is necessary," said Chief Presidential Legal Counsel Salvador Panelo in a text message to reporters Wednesday.

The Supreme Court upheld the legality of Duterte’s martial law proclamation on Tuesday.

The 60-day period for martial law declaration will expire on July 22.

In the "Mindanao Hour" press briefing in Malacanang, military spokesman Brig. Gen. Restituto Padilla said the Armed Forces of the Philippines has set parameters whether it would recommend the extension of martial law.

"We have set conditions that would specifically mention or act as the standards whether martial law should be extended or not...and that assessment regarding whether those conditions have been met has not yet been made fully. It will be made in about a week and a half or two," he said.

Asked what could be the parameters, he said, "we do not want to lay those cards yet. Let’s give our operational guys the opportunity to do their homework first. Because that was very specific in some of the publications that I am not at liberty to discuss at the moment."

Meanwhile, Padilla said two foreign-looking cadavers were recovered on Tuesday in Marawi.

"Initially, they said it was the remains or this could be the remains of a foreign fighter and allegedly a Singaporean. But we don’t have yet enough proof to validate this information and we are working to do that along with the police," he said.

"But this goes to show that indeed, there are foreign fighters who are in the area fighting alongside the group --- the terrorist group inside," he added.

During the first week of military offensive operations in Marawi, the military claimed eight foreigners, including Malaysians and Indonesians, were killed. Celerina Monte/DMS