More than 50 civilians have been killed, almost half of them children, since unrest with neighboring Pakistan escalated last week, UN human rights chief Volker Türk said in a statement on Friday.
"I urge all parties to end the conflict and to prioritize helping those in extreme need," he said.
The neighboring countries have clashed along the border since February 26, when Afghanistan launched a border offensive in retaliation for Pakistani airstrikes.
Pakistan, in turn, has hit back with new attacks, bombing several locations, including the capital, Kabul, the U.S. air base at Bagram and the southern city of Kandahar in Afghanistan.
