More than 3000 civilians were killed in the war in Afghanistan in 2011, the fifth year in a row the figure has risen, the UN said yesterday.

Civilian deaths undermine support in Afghanistan and America for the US-led war, and are one of the biggest causes of friction between President Hamid Karzai and the Nato-led International Security Assistance Force.

Bombs planted on roads and suicide attacks killed more civilians than any other type of attack, according to the UN Assistance Mission in Afghanistan.