Ban, on a trip to Bosnia, also visited the Sarajevo stadium used in the 1984 Winter Olympics and said the U.N. had learned its lessons on its responsibility to halt mass killings.
"Now that we have understood the message of Srebrenica, we must do everything possible to stop the slaughter in Syria," Ban said at the Potocari cemetery where he placed white flowers at the memorial outside Srebrenica. "The international community was incapable of protecting those who in that moment needed our help, and they were killed."
Ban was accompanied to the cemetery by Bosian President Bakir Izetbogovic, a Muslim who heads the country's three-party presidency," the Italian news agency ANSAmed reported. Ban is on a weeklong trip to the Balkan countries created from the former Yugoslavia.