The US-led NATO force in Afghanistan pledged Saturday to continue efforts to locate and return an American army sergeant who was kidnapped by the Taliban three years ago.

Bowe Bergdahl, now believed to be 26, was taken prisoner by the Taliban in the southeastern province of Paktika on June 30 2009, and was subsequently officially declared as "Missing-Captured" by the United States.

"Today marks three years that U.S. Army Sergeant Bowe W. Bergdahl has been held captive," Brigadier General Lewis Boone, director of Public Affairs for US Forces-Afghanistan, said in a statement.

"A member of the U.S. military is missing and we will continue to expend significant efforts to locate Sgt. Bergdahl and return him home," he added.

ISAF said that "yellow ribbons" had been tied "on trees, fence posts, and light poles" in Bergdahl's hometown of Hailey, Idaho.

"We would like nothing more than to see them come down because he is returning home to the people who love him," Brig Gen Boone added.

Bergdahl, who the Taliban claimed had been drinking alcohol when they captured him, is believed to be the only NATO member to have been taken captive by insurgents in Afghanistan since the war began in 2001.

On July 19 2009, the Taliban released a video of him, in which he was shown siting on the floor in traditional pale grey Afghan clothing, pleading for US troops to leave the war-torn nation.

There are presently around 130,000 US-led NATO forces fighting a decade-long Taliban led insurgency in Afghanistan.

Despite a stubborn Taliban insurgence, war-weary international forces are seeking to hand control of security to Afghan forces by withdrawing their combat troops by the end of 2014.