Obama's decision is largely in line with what military commanders have been seeking and will allow the president to fully end the American-led military effort by the time he leaves office.
The two-year plan is contingent on the Afghan government signing a bilateral security agreement with the U.S. While current Afghan President Hamid Karzai has declined to sign the agreement, U.S. officials are confident that either of the candidates seeking to replace him would give his approval.
The plan calls for the U.S. military to draw down from its current force of 32,000 to 9,800 by the start of next year. Those troops, dispatched throughout Afghanistan, would focus on counterterrorism and the training of Afghan security forces. They would not be engaged in combat missions.
Over the course of next year, the number of troops would be cut in half and consolidated in the capital of Kabul and at Bagram Air Field, the main U.S. base in Afghanistan. Those remaining forces would largely be withdrawn by the end of 2016, with fewer than 1,000 remaining behind to staff a security office in Kabul.
The American forces would probably be bolstered by a few thousand NATO troops. The total NATO presence, including U.S. troops, is expected to be around 12,000 at the start of next year.
Obama was to announce the plan at the White House Tuesday afternoon. He is just back from a surprise weekend trip to Afghanistan where he met with U.S. commanders and American forces serving in the closing months of America's longest war.
The officials providing details of the announcement insisted on anonymity because they were not authorized to discuss the plan by name ahead of the president.
Ahead of his remarks, Obama was expected to speak with Karzai, who has had a tumultuous relationship with the White House. The two leaders did not see each other while Obama was in Afghanistan, but they did speak by phone as Air Force One was returning to Washington.
Obama has also discussed his plans with several European leaders, including German Chancellor Angela Merkel, British Prime Minister David Cameron and Italian Prime Minister Matteo Renzi.
U.S. military commanders have been arguing for months to keep roughly 10,000 troops in Afghanistan, if only for a limited time, while they bolster the Afghan forces' ability to do long-term logistical planning and increase their air force capabilities. In recent weeks, the military had expressed confidence that they had been able to sell their plans to the White House.
Germany and Italy have said they will continue as lead nations in the north and west of Afghanistan, and there has been some discussion that the U.S. would also have some troops in those areas to work with the allies.
After Karzai refused to sign the bilateral security agreement, Obama asked the Pentagon to plan for the possibility that all American forces would withdraw by a year-end 2014 deadline. But given the supportive comments of the candidates in Afghanistan's presidential election, Obama signaled during his holiday weekend trip to Bagram that he was likely to keep some American troops in the country.
"After all the sacrifices we've made, we want to preserve the gains that you have helped to win, and we're going to make sure that Afghanistan can never again, ever, be used again to launch an attack against our country," Obama declared.
At least 2,181 members of the U.S. military have died during the nearly 13-year Afghan war and thousands more have been wounded.
Associated Press writer Lolita C. Baldor contributed to this report.
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