US Weighs Slowing Afghan Withdrawal to Ensure Progress Sticks: Carter

Under the current plan, the United States will halve the number of troops in Afghanistan to just over 5,000 this year, gradually winding down to a "normal" US embassy presence by the end of 2016.

That schedule could now change, at least in part, suggested Carter on his first trip abroad since swearing in as the Pentagon chief on Tuesday, as the United States also rethinks the future of its counter-terrorism mission in Afghanistan.

His remarks set the stage for talks next month when the Afghan president is expected in Washington.

"Our priority now is to make sure this progress sticks," Carter said at a joint conference with President Ashraf Ghani, hours after landing in Kabul.

"That is why President (Barack) Obama is considering a number of options to reinforce our support for President Ghani's security strategy, including possible changes to the timeline for our drawdown of US troops."

Ghani said he expected to discuss US troop numbers with Obama "in the context of the larger partnership."

US General John Campbell, who leads international forces in Afghanistan, suggested his focus for now was sustaining enough US trainers, advisors and counter-terrorism forces in Afghanistan during 2015 and 2016, not what happens later.

"Right now I think we're comfortable looking at '15 and '16," Campbell told reporters traveling with Carter.

The current strategy has drawn sharp criticism from Republicans in Congress, who say that hard-won gains made against the Taliban could be lost in much the same way that violence returned to Iraq after the US withdrawal, Reuters reported.

Afghanistan's national army and police suffered heavy losses last year, the bloodiest since the war against Taliban militants began in 2001.