Metro Manila (CNN Philippines) — President Rodrigo Duterte gives U.S. President Obama a piece of advice on Friday — as the former mayor marks his 100 days in Malacañang.

Speaking at the National Banana Congress in Lanang, Davao City, Duterte said Obama should go through diplomatic channels when complaining about the Philippine government's war against illegal drugs.

"So, if you want Mister Obama, you can ask your representative to the U.N. to make a complaint," he said. "I am not your servant. Do not do it to me. I am the President of the Republic of the Philippines."

As for the European Union, Duterte said it was "too far away" and repeated what he said yesterday about not being afraid if the U.S. or EU would decide to pull out aid to the Philippines.

"Who do you think you are? Without your aid, fine. We will survive."

In contrast, the firebrand president had only good words for China, saying he was positive about his forthcoming visit to the Asian superpower.

"It is only China who has helped us. I requested the military to open their camps to allow people who would want to donate rehab houses. China is about to complete Sobrosa... It would house 1,400 drug addicts."

Rating his own performance

After surveys showing high ratings for his first hundred days in office and war against drugs, Duterte gave himself a mere passing mark.

Related: Duterte bags 'very good' satisfaction rating, SWS says

"Dyan lang ako naglalaro eh. Ever since kindergarten, 75-76. Hwag lang bumagsak."

[Translation: My grade had always been around the vicinity of 75-76. Just so as not to flunk.]

Or in a scale of 1 to 10 — with 10 being the highest — the President said he was giving himself a six.

CNN Philippines' Anjo Alimario contributed to this report.