American officials say the United States President is poised to announce on Thursday the withdrawal of up to 10,000 US troops from Afghanistan by the end of this year.
Barack Obama will use a prime-time television address to unveil plans for an initial withdrawal of thousands of US troops from Afghanistan.
US media say he is expected to say that 30,000 "surge" troops will begin leaving in July, with most gone by 2013.
The US currently has about 100,000 troops in Afghanistan.
Divisions remain within the Obama administration over the size and speed of the pull-out.
Military commanders are thought to want to limit the number of combat troops removed from the country in an effort not to lose ground gained from the Taliban during recent fighting.
Reports of Mr Obama's announcement come after departing US Defence Secretary Robert Gates confirmed that the US was holding "outreach" talks with members of the Taliban in Afghanistan. It was the first time the US had acknowledged such contact.