SENATE President Francis Escudero on Monday said the Senate holds the primary authority in matters of impeachment, noting its decisions would take precedence over any rulings made by the Supreme Court.

Escudero said that in 2003, the House of Representatives proceeded with the impeachment of Chief Justice Hilario Davide Jr. despite a temporary restraining order issued by the Supreme Court.

On the other hand, he noted that the Senate adhered to a court order by not opening foreign currency deposit accounts during Chief Justice Renato Corona's impeachment trial in 2011.

Escudero welcomed the willingness of Senate Minority Leader Koko Pimentel to lead the drafting of revised impeachment rules for the upcoming impeachment trial against Vice President Sara Duterte.

"I welcome and thank Senator Pimentel's offer to help draft the proposed rules. I will instruct the legal team to coordinate with him on this matter. He emphasized that all proposed rules would require approval from the plenary or the Impeachment Court once proceedings resume," he said.

Meanwhile, former education undersecretary and chief of staff Michael Wesley Poa has entered his appearance as one of the lawyers of Duterte in her petition to stop her impeachment before the Supreme Court.

"I confirm that I filed my entry of appearance as co-counsel of the vice president in relation to her petition for certiorari and prohibition before the Supreme Court" Poa told The Manila Times on Tuesday.

Poa would join the vice president's legal team that includes her father, former president Rodrigo Duterte and her father-in-law, Lucas Carpio Jr., as well as veteran lawyers Sigfried Fortun, Gregorio Narvasa, Sheila Sison and Roberto Batongbacal.

In her petition, Duterte asked the high court to stop her impeachment, saying the House of Representatives committed "grave abuse of discretion amounting to lack or excess jurisdiction."

Duterte was impeached by at least 215 members of the House of Representatives on Feb. 5 due to allegations of bribery, betrayal of public trust, high crimes, conspiracy and alleged involvement in extrajudicial killings.

Meanwhile, lawyer Rene Sarmiento said that the six months delay in the impeachment trial was "unreasonable."

He said that the "forthwith" provision in the Constitution to immediately start the impeachment trial is a "command" and meant to deter abuses by government officials.

Sarmiento, a member of the commission that drafted the 1987, said in a radio interview that all rules, laws, and policies "must bow to the Constitution" in line with the doctrine of constitutional supremacy.

He said there should be no delay in the impeachment trial because the issue of accountability in government is important.

Sarmiento added that many members of the constitutional commission are with him that "forthwith" means immediately.