Senator Antonio Trillanes IV warned on Sunday other Supreme Court justices who would try to remove embattled Chief Justice Maria Lourdes Sereno other than impeachment that they could face similar impeachment proceeding.

Trillanes made the remark following reports that certain high court magistrates, headed by Associate Justice Marvic Leonen, were maneuvering to force the "unconstitutional" removal of Sereno.

"Any attempt to remove the Chief Justice through a process other than impeachment is unconstitutional. It will be a brazen usurpation of the exclusive power of Congress under the Constitution," he said in a statement.

"May I remind these justices that any unconstitutional act they commit now, can be used as a ground for impeachment against them later on under a different administration. For those who are retired by then, these acts can and will be used as basis for graft cases," he added.

Sereno, who is on an "indefinite leave," is facing an impeachment complaint before the House of Representatives.

The House is expected this week to decide on the complaint.

The House committee on justice, which has been hearing the complaint against Sereno, has started drafting the articles of impeachment against the chief justice.

According to Sereno, who refused to heed calls for her to quit, she would answer all the allegations against her when she is impeached and her case is tried by the Senate, sitting as an impeachment court.

Sereno has been accused of culpable violation of the Constitution, betrayal of public trust, commission of high crimes, and corruption.

Specifically, she allegedly failed to submit her statements of assets, liabilities and net worth to the Judicial and Bar Council when she applied as the chief magistrate in 2012, among others. Celerina Monte/DMS