The International Criminal Court's chief prosecutor says she is "deeply concerned" about reports of extrajudicial killings of suspected drug dealers and users in the Philippines and that statements by "high officials" in the Asian nation "seem to condone such killings."

The written statement Thursday by Prosecutor Fatou Bensouda appeared aimed as a blunt warning to Philippine President Rodrigo Duterte, whose anti-drug crackdown has left an estimated 3,000 people allegedly involved in the drug trade dead.

The International Criminal Court is the world first global court prosecuting war crimes and crimes against humanity.

In her statement, Bensouda says that "any person in the Philippines who incites or engages in acts of mass violence...within the jurisdiction of the ICC is potentially liable to prosecution before the Court."