MANILA (UPDATE) – The leader of the opposition party on Friday sought greater transparency from Malacañang after President Rodrigo Duterte’s absence from public light for much of the week triggered questions and concerns about his health.

In a statement, Sen. Francis Pangilinan, president of the Liberal Party, said the Palace should come clean if there was anything ailing the chief executive.

“While I accept the explanation of Malacañang that he was tired and needed rest, the four-day absence was a concern considering the current situation,” said Pangilinan, in apparent reference to the ongoing crisis in Marawi City.

“Having said that, if the President has a medical condition preventing him from fulfilling his duties as commander-in-chief and is not simply 'just resting,' then the public deserves to know the truth,” he said.

Malacañang on Thursday released photos of President Duterte working at his official residence in Manila amid speculation on his health following days of absence in public events.

Later, it also released photos of Duterte during a visit at the Villamor Air Base, showing the president smiling as he shook hands with an officer and another saluting Air Force officials.

The president later flew to Davao City.

The president’s last public outing was at the Villamor Air Base in Pasay City on Sunday, where he honored troops who died fighting terrorists in Marawi City.

Malacañang had earlier explained that 72-year-old Duterte, the oldest to become president, was just “tired” and taking a rest following a grueling schedule last week. He missed the 119th Independence Day rites on Monday, supposedly his first to mark as president.

In explaining Duterte’s extended break, presidential spokesperson Ernesto Abella said earlier Thursday that the president was not dealing with any “major sickness.”

Before his break, Duterte had spent much of his time in Mindanao, rallying troops in southern camps amid the continuing offensive against Islamic State-linked terrorists from the Maute and Abu Sayyaf Groups.

The firefights, now into the fourth week, have left nearly 300 dead, among them 58 government troops and 26 civilians.

Duterte declared martial law over all of Mindanao after clashes erupted on May 23.

Maria Fe Villamejor-Mendoza, dean of the University of the Philippines National College of Public Administration and Governance, also sought disclosure of the president's health status.

Mendoza said this was the president's "obligation" so the public would not get "worried."

"'Yung hugot dun kasi yung sa martial law di ba? Matagal na tinago sa mga tao yung state of health ni former President [Ferdinand] Marcos. Tapos ang ano dun, marami kasing agam-agam baka may shadow cabinet," she said.

She said Article VII of the 1987 Constitution mandated a sitting president to disclose his health condition, and President Duterte should comply.

"In terms of transparency at paglalahad ng katotohanan, siguro maraming naghahanap. Kasi kung palagi naman si President Duterte in the limelight kahit nga medyo gabi... then all of a sudden nawala siya," she said.

Mendoza noted that no one one may prevent the president from taking a break given his age and "punishing schedule." But, she said, public disclosure of his health status was necessary.

This is important as Filipinos are oriented to looking up to a "top figure."

"Sabihin din nila para walang agam-agam ang publiko kung ano nga ba ang sitwasyon ng presidente ngayon... Presidente siya at siya ang pinakapuno ng bansa. So obligasyon na ipaalam ang kanyang kalusugan," she said.

It would also be ideal if the president's personal physician would be the one to discuss what's happening to Duterte instead of his cabinet secretaries or spokespersons, she said. -- with reports from Sherrie Ann Torres, ABS-CBN News