KABUL: The Taliban have welcomed news from Washington that the US might withdraw all its troops from Afghanistan next year, saying the American public was pressing for an end to "this aimless war".

The comment came ahead of a crucial meeting between President Barack Obama and Afghan President Hamid Karzai at the White House on Friday that is expected to focus on how many American soldiers will remain in Afghanistan.

The US and its NATO allies have long planned to withdraw their combat troops by the end of 2014, although it has been widely expected that Washington will leave a force to train, advise and assist the Afghan army and police.

But Ben Rhodes, a deputy national security adviser, told reporters Tuesday that Obama would not rule out any ideas, including the so-called zero option -- pulling out all the remaining 66,000 US troops.

US military officers privately said comments about a total withdrawal were primarily designed as a tactic in negotiations with Kabul over a security agreement, which includes immunity for American troops remaining behind.

Taliban insurgents, however, seized on Rhodes' comments as a sign that the administration was under pressure from the American people to pull out completely from the nation's longest war.

"We appreciate this step of the American public and all those societies who pressurise their government in the issue of Afghanistan as to bring this aimless war to an end and to evacuate all their troops," the Taliban said in a statement on their website.

Opinion polls for several years have shown that the US public is tired of the human and financial cost of the Afghanistan war, initially launched after the September 11, 2001, attacks on the United States.