**The top US military commander in Afghanistan, Gen Stanley McChrystal, has formally requested more forces.**The Pentagon said it would put the request on hold until President Barack Obama decides what overall strategy to pursue in Afghanistan.
President Obama has already sent 21,000 extra troops to Afghanistan this year.
In a report leaked last month, Gen McChrystal wrote that his mission was likely to fail if he was not given extra troops.
The US currently had more than 60,000 soldiers in Afghanistan.
Exact figures for the requested reinforcements have not been revealed, although reports suggest that figure could be 30,000.
Correspondents say White House advisers are split over whether to extend America’s commitment in Afghanistan.
President Obama has described himself as “a sceptical audience” to sending more soldiers, and says he wants to be sure the current strategy is correct first.
A Gallup poll published on Friday showed a fall in support for the war in America, with 50% opposed to sending more troops, while 41% supported it, reports say.