President Barack Obama's plan to withdraw 34,000 US troops from Afghanistan within a year was based on the advice of former commander General John Allen, Pentagon chief Leon Panetta said Tuesday.
The Pentagon chief said he welcomed Obama's announcement in his State of the Union address on the decision sharply reduce American forces, which make up about two thirds of the NATO-led International Security Assistance Force.
"This plan to continue drawing down our forces in a phased approach over the coming year was recommended by General Allen based on a thorough assessment of the ISAF campaign plan moving forward," Panetta said in a statement.
The defense secretary's comments appeared aimed at countering criticism from some Republicans in Congress that Obama has allegedly ignored military advice and crafted withdrawal plans based on political considerations.
On Sunday, Allen officially handed command of ISAF to General Joseph Dunford, who is expected to be the last US commander in Afghanistan as Western countries prepare to depart by the end of 2014, when NATO's mission ends.
The war effort is on a promising path "to achieve the goal of this campaign - to deny Al-Qaeda a safe haven to attack our homeland," said Panetta, who is due to retire within days pending the Senate's confirmation of his nominated successor, former senator Chuck Hagel.
With NATO planning to hand over to Afghan forces in 2014, Panetta said the coalition troops "are on track for that goal."
He also said the United States "will maintain a long-term commitment to Afghanistan -- including through the continued training and equipping of Afghan forces and counterterrorism operations against Al-Qaeda and their affiliates."
The troop drawdown schedule presented by Obama reflects the best military advice at the Pentagon and in Afghanistan, defense officials said.
"The commanders will have discretion on the pace" of the withdrawal and the "focus will be keeping as many forces in play until after the fighting season" ends in the autumn, said a senior defense official, who spoke on condition of anonymity.
Under Obama's plan, the current US force of roughly 66,000 would be scaled back by half within 12 months, to about 32,000.
In 2009, Obama ordered in a surge of more than 30,000 reinforcements, bringing the American presence to a peak of about 100,000 boots on the ground.