In a watershed moment for American foreign policy, Obama also significantly curtailed US war aims, saying Washington would no longer try to build a "perfect" Afghanistan from a nation traumatized by its blood soaked history.

"Tonight, we take comfort in knowing that the tide of war is receding," Obama said in 13-minute primetime speech at a time of rising fatigue over costly foreign wars among Americans ground down by deep economic insecurity.

"Even as there will be dark days ahead in Afghanistan, the light of a secure peace can be seen in the distance. These long wars will come to a responsible end," Obama said.

The president argued US forces had made large strides towards the objectives of the troop surge strategy he ordered in December 2009 by reversing Taliban momentum, crushing Al-Qaeda and training new Afghan forces.

AFP