A decision on immunity for U.S. troops staying in Afghanistan after the 2014 planned withdrawal will be made by the end of the year, Afghan President Hamid Karzai said on Monday.

"The issue of immunity is under discussion (and) it is going to take eight to nine months before we reach agreement," Karzai told a news conference in the capital, Kabul, after returning from meetings with U.S. President Barack Obama in Washington.