No 'exit strategy'
But the US president, who on Friday announced a timetable for the withdrawal of US troops from Iraq, declined to set a timeline on when US troops would exit Afghanistan.
"Until we have a clear strategy, we're not going to have a clear exit strategy," he said.
"My goal is to get US troops home as quickly as possible without leaving a situation that allows for potential terrorist attacks against the United States," Obama said.
Anti-war critics have condemned the Afghanistan deployment, fearing that the US could get bogged down in an another conflict.
Hillary Clinton, the US secretary of state, convened a three-way meeting with the Afghan and Pakistani foreign ministers earlier this week as part of a review on US policy toward the two nations.
The US has once again focused on Afghanistan in attempt to defeat Taliban and al-Qaeda fighters who have mounted a resurgent campaign in the border region with Pakistan.