US Defense Secretary Robert Gates has left open the possibility of sending more forces to Afghanistan but warned of stretched military resources.
With about 132,000 troops in Iraq, Gates said there were constraints as to how many extra troops could be sent to Afghanistan at least until after Iraq's elections in January.
"I would say also that the availability of forces is still a challenge," he told a news conference on Thursday.
Referring to plans to reduce US troops in Iraq over the next year, Gates said that "until the more accelerated drawdown in Iraq begins after the elections there ... it will be a challenge for us."
