US unable to spare Afghan troops
The US has 33,000 troops in Afghanistan
Three extra combat brigades requested by the US commander in Afghanistan will not be available before spring 2009, the US defence secretary has said.
The US does "not have the forces... at this point", Robert Gates told the Senate Armed Services Committee.
Last week Gen David McKiernan, the head of the Nato-led force in Afghanistan, said he needed three more brigades on top of planned troop increases.
About 6,000 extra troops are set to arrive over the next four months.
"Without changing deployment patterns, without changing length of tours, we do not have the forces to send three additional brigade combat teams to Afghanistan at this point," Mr Gates told the committee.
"Those forces will become available probably during the spring and summer of 2009," he said.
The US has some 33,000 troops in Afghanistan, including 13,000 under the command of Nato.