"UNICEF strongly condemns the abduction and killing of three Israeli young people in the West Bank," Xinhua quoted a statement as saying.
"This latest act of violence is a tragic and terrible reminder of the toll that senseless hatred is taking on both Israeli and Palestinian children," the statement said.
"We urge all parties to exercise the utmost restraint, and do everything in their power to protect all children, Palestinian and Israeli from harm."
On Monday, UN Secretary-General Ban Ki-Moon strongly condemned the murder of the three Israeli teenagers abducted in the West Bank, calling it a "heinous act".
"There can be no justification for the deliberate killing of civilians," Ban said in a statement.
The Israeli security forces on Monday discovered the bodies of three Israeli teens, who went missing June 12, near Hebron in the West Bank.
The bodies of 19-year-old Eyal Yifrach and 16-year-old Naftali Frankel and Gilad Shaer, were found in an area controlled by the Palestinian authority, not far from where they were supposedly abducted.