Serbia on Saturday said an attack on its prime minister at a ceremony marking the Srebrenica massacre 20th anniversary was an "assassination attempt" and demanded condemnation of the incident by Bosnia.

"We expect a public condemnation by Bosnia's authorities of the assassination attempt on the Serbian prime minister," the foreign ministry said in a protest note handed to their Bosnian counterparts. Prime Minister Aleksandar Vucic told reporters a stone hit his mouth but he was not hurt.