Prior to the Japanese leader's departure from Tokyo's Haneda airport, Abe said he wanted to exchange candid views while in Iran and help ease rising tensions.
In a statement, Panelo defended President Rodrigo Duterte's crackdown on illegal drugs, which the UN says has led to over 27,000 deaths since the campaign began in June 2016.
The police raids were criticized by the opposition and by media associations, which see them as an attempt to intimidate journalists and whistleblowers who leak information.