"The International Criminal Court cannot arbitrarily interfere in the domestic affairs of a sovereign country like the Philippines," Abella said.
He then pointed out the lack of evidence supporting the claims the ICC made, even mentioning the Senate, who earlier ruled that President Rodrigo Duterte had no hand in the alleged crimes.
"There is no concrete evidence pointing to crimes against humanity here: such crimes must be widespread and systematically directed against a specific group. This element is absent in the Philippine situation," he said. "The Philippine Senate already absolved the President and there exists no such crime."
Related: Senate report: No 'DDS,' no Duterte hand in killings
In October last year, ICC chief prosecutor Fatou Bensouda expressed "deep concern" over the alleged extrajudicial killings in the Philippines' drug war.
She said her office "will be closely following developments in the Philippines in the weeks to come and record any instance of incitement or resort to violence."
Related: Int'l Criminal Court chief prosecutor warns PH over drug killings
President Duterte responded in November that he might withdraw from the ICC, following the footsteps of Russian President Vladimir Putin.
Related: Duterte: I might follow Putin's ICC withdrawal
Former Foreign Secretary Perfecto Yasay later supported Duterte's statement, saying the President might push through with the withdrawal if the ICC continues to criticize the country's drug war.
The ICC, located at the The Hague in Netherlands, is a "court of last resort" tasked with trying crimes if a member state's national justice system is unable or unwilling to address an issue.
The court limits itself to trying the "gravest crimes" -- genocide, crimes against humanty, crimes of aggression, and war crimes.
It was established in 1998 through the creation of the Rome Statue, and has 124 countries party to the treaty.
While it was not created to replace local judiciaries, it exercises the authority to intervene if a state fails to investigate and prosecute perpetrators of crimes within its jurisdiction.
SOURCE: CNN, YOUTUBE