Metro Manila (CNN Philippines, June 29) — The Supreme Court is giving President Rodrigo Duterte 10 days to comment on an ouster petition filed against him, sources told CNN Philippines.

"We will respond as ordered," Presidential Spokesperson Harry Roque said in a statement.

The quo warranto petition was filed by suspended lawyer Elly Pamatong against Duterte on June 6.

The same petition, a legal proceeding where an individual's right to hold office is challenged, was used to permanently remove Maria Lourdes Sereno from the Chief Justice post on June 19.

Pamatong in his petition said Duterte's certificate of candidacy during the 2016 elections was "illegal," stripping him of any constitutional authority to serve as President.

Duterte's COC was filed late and was not even approved by the Commission on Elections sitting en banc, he added.

Duterte ran as a substitute candidate for former PDP-Laban standard bearer Martin Diño, a move that was allowed by Comelec when it dismissed the disqualification cases against Duterte.

In 2016, the Supreme Court slapped Pamatong with a two-year suspension from practicing law after calling a judge "corrupt."