MANILA: A Philippine impeachment court on Tuesday (Oct 13) granted prosecutors' request to drop two charges against Vice President Sara Duterte, including an alleged assassination threat against the president, leaving accusations of unexplained wealth the sole remaining count against her.

Prosecutors, who last week requested a bribery charge be removed from the case, asked Tuesday that allegations of misused funds and a death threat made against President Ferdinand Marcos also be eliminated.

Sara Duterte, daughter of former president Rodrigo Duterte been on trial before the Philippine Senate for months with conviction on any of four charges carrying a punishment of barring her from elected office permanently.

The court is still weighing the last remaining charge, and thus she could still be hit with a ban that would end her bid to become president in 2028 if found guilty.

"Articles 1, 3, and 4 shall no longer form part of the Articles of Impeachment ... shall not be submitted to the members of the court for a vote or for a verdict of conviction or acquittal," Senator and presiding officer Francis Escudero said in approving the motion.

The unexpected move by prosecutors on the trial's 39th day came after they presented weeks of evidence backing the now-dismissed charges. "COMPLETELY UNFAIR" Chief prosecutor Gerville Luistro told the tribunal the decision would ease the court's job and speed up the conclusion of the trial, which began on Jul 6.

"The prosecution believes it has presented sufficient evidence for Article 2 (unexplained wealth) to stand on its own," Luistro said, referring to allegations that Duterte had failed to declare all her assets, something government officials are required by law to do each year.

"We're going all in here. We believe that the evidence is substantial and compelling and warrants the respondent's removal from office." Chief defence lawyer Sheila Sison called the ruling "completely unfair", noting prosecutors had already put 14 witnesses on the stand to lay out evidence against the vice president.

Last month, in a ruling widely seen as a blow to Duterte, the 24-seat Senate approved a lower threshold of votes needed to find her guilty, potentially making it easier to execute her ouster.

With at least four senators loyal to the vice president now absent from the trial - two in jail, another in hiding and a fourth on extended medical furlough abroad - only 14 votes are needed to find her guilty.

Senators voted that the constitutionally required two-thirds guilty verdict by "all members of the Senate" referred only to those "capable of participating".

Despite her impeachment by the House of Representatives, the vice president remains firmly in the lead in polling for the 2028 presidential election, independent surveys show.