In an interview Monday with the BBC, Gen. David Petraeus restated his commitment to a conditions-based troop withdrawal from Afghanistan and emphasized that next year's deadline is "not the date when the American forces begin an exodus."

Since becoming top commander in Afghanistan in June, Petraeus has frequently been asked to assess the country's prospects for security in light of what many consider a countdown until next summer. 

Speculation also mounted last week as combat forces began their final withdrawal from Iraq.

Petraeus said Monday that the momentum of the Taliban has been reversed in many parts of the country, but fighting will remain intense near the remaining strongholds. 

Asked if the withdrawal plan might require delays, he said, "Come July 2011, I will offer the president my best professional military advice."

He also said that he would "speak out" if the plan proved too risky in a year.