WASHINGTON - US President Barack Obama defended his Afghanistan policy Wednesday, as the central Asian nation is embroiled in anti-American unrests stemming from inappropriate handling of religious material by US soldiers.

In an interview with US broadcaster ABC at the White House to be aired later in the evening, Obama said he is "confident" the United States will be able to stay on the path that will gradually withdraw troops and handing over the security lead to Afghan forces by the end of 2014.

"War is a tough business, and never goes in a perfectly good path. But because of the stick-to-it-ness of our teams, I feel confident that we can stay on a path that, by the end of 2014, our troops will be out and will not be in a combat role, and Afghans will have capacity, just as Iraqis, to secure their own country," said Obama, according to excerpts made available by ABC.

Obama said his formal apology to Afghan President Hamid Karzai for the burning of Koran by US troops last week, is aimed at curbing further danger to US troops on the ground. He said it has "calmed things down" after the incident sparked an outbreak of violence across the country, but the US side is "not out of the woods yet."

"As difficult as Afghanistan has been, we are making progress because of the extraordinary service of our men and women in uniform," Obama claimed. "The overwhelming majority of Afghan troops have welcomed and benefitted from the training and partnering that we're doing."