MANILA — A human rights lawyer on Thursday slammed the Philippines government's supposed opposing actions in its case before the International Criminal Court regarding former President Rodrigo Duterte's war on drugs.

ICC Prosecutor Karim Khan has rejected the grounds raised by the Philippine government in its appeal before the ICC Appeals Chamber, opposing the country’s move to halt the ICC probe.

"Namamangka sa dalawang ilog," Ruben Carranza, senior expert of New York-based International Center for Transitional Justice, told ANC's "Rundown".

"You want to appeal the prosecutor's authority to investigate that the ICC chambers, that the court has already authorized to resume. On the other hand, you are also threatening that you will no longer participate if your appeal is decided against you," he added.

• ICC Prosecutor opposes PH’s grounds in ICC appeal over drug war probe

Solicitor General Menardo Guevarra, in a statement, said the government would reply to the ICC to show what he dubbed as "the shallowness of the prosecutor's response".

Justice Secretary Jesus Crispin Remulla, meanwhile, echoed President Ferdinand Marcos, Jr.'s previous remark that the government would no longer engage with the ICC.

Carranza described this as "most unlawyerly".

He stressed the Marcos administration had opted to participate in the litigation involving these possible crimes against humanity.

In March, the Philippine government hired a British lawyer to help the country in its appeal to the ICC.

Carranza noted the UK-based law firm 9 Bedford Row also represented Kenya’s deputy president William Ruto in the latter's charges of crimes against humanity before the ICC.

In the interview, the international justice expert also backed Khan's decision.

Khan said Manila failed to show that the ICC Pre-Trial Chamber erred in authorizing the resumption of the investigation.

"The Philippines' argument essentially is that we already withdrew even if the crimes were already committed... our withdrawal ends your authority, ICC, to investigate those killings," Carranza said.

"It's a very basic argument that the prosecutor has made against that. The killings happened before you withdrew.

"In any situation involving courts, even if you were to say I will no longer recognize the authority of this court, which is what the Philippines is saying, the fact is that at the time these crimes were committed, the Philippines recognized the authority of the court to investigate," he added.

• ICC approves resumption of probe into PH drug war, Davao killings
• PH appeals resumption of ICC probe into drug war killings

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