"The desecration of any holy text, including the Quran, is an act of extreme intolerance and bigotry," Obama said in a statement on Saturday evening.At the same time, he said that to attack and kill innocent people in response is "outrageous" and "an affront to human decency and dignity."
The US president was referring to violent protests in Afghanistan against the burning of a Quran by pastor Terry Jones in a small Florida church. Ten people died on Saturday in Kandahar, a day after seven United Nations staff were killed by an armed mob in Mazar-e-Sharif.
No religion tolerates "the slaughter and beheading of innocent people" and there is no justification for "such a dishonourable and deplorable act," Obama said.
"Now is a time to draw upon the common humanity that we share, and that was so exemplified by the UN workers who lost their lives trying to help the people of Afghanistan," he said.
"Today, the American people honour those who were lost in the attack on the United Nations office in Mazar-e-Sharif, Afghanistan. Once again, we extend our deepest condolences to the families and loved ones of those who were killed, and to the people of the nations that they came from," Obama said.