REPUBLIKA.CO.ID, WASHINGTON - The number of US troops in Afghanistan may drop well below 10,000 - the minimum demanded by the US military to train Afghan forces - as the longest war in American history winds down, Obama administration officials briefed on the matter say.

Since Afghanistan's general election on April 5, White House, State Department and Pentagon officials have resumed discussions on how many American troops should remain after the current US-led coalition ends its mission this year.

The decision to consider a small force, possibly less than 5,000 US troops, reflects a belief among White House officials that Afghan security forces have evolved into a robust enough force to contain a still-potent Taliban-led insurgency. The small US force that would remain could focus on counter-terrorism or training operations.

That belief, the officials say, is based partly on Afghanistan's surprisingly smooth election, which has won international praise for its high turnout, estimated at 60 percent of 12 million eligible votes, and the failure of Taliban militants to stage high-profile attacks that day.

The Obama administration has been looking at options for a possible residual US force for months.

"The discussion is very much alive," said one US official who asked not to be identified. "They're looking for additional options under 10,000" troops.

There are now about 33,000 US troops in Afghanistan, down from 100,000 in 2011, when troop numbers peaked a decade into a conflict originally intended to deny al Qaeda sanctuary in Afghanistan after the September 11, 2001, attacks.

With British and other foreign troops scheduled to depart in lock step with US soldiers, the size of any residual US force could add fuel to a debate in Washington over whether Taliban-led violence will intensify amid the vacuum left by Western forces, as some US military officials expect.