Washington (CNN) -- The United States is quickening the rate at which it is stepping back in Afghanistan.
On Friday, President Barack Obama and Afghan President Hamid Karzai agreed to speed up the military transition in that country, meaning Afghan forces will take the lead in combat operations nationwide starting this spring.
That transition was previously seen happening mid-year.
"What's going to happen this spring is that Afghans will be in the lead throughout the country. That doesn't mean that coalition forces including U.S. forces are no longer fighting," Obama said. "They will still be fighting alongside Afghan troops. It does mean though that Afghans will have taken the lead and our presence, the nature of our work will be different. We will be in a training, assisting, advising role.
"It will be a historic moment and another step toward full Afghan sovereignty."
The two presidents spoke to reporters in the White House East Room. The mood was cordial, belying the tense relationship of years past.
Besides the accelerated timetable, Obama and Karzai agreed that the United States would hand over full control of Afghan prisoners. That demand had been a major sticking point for Karzai, who in return signaled he could be willing to consider immunity for U.S. forces beyond 2014.
"I can go to the Afghan people and argue for immunity for U.S. troops in Afghanistan in a way that Afghan sovereignty will not be compromised, in a way that Afghan law will not be compromised," he said.
The United States plans to pull all combat troops from Afghanistan by the end of next year. There is discussion, however, of keeping a residual force there to help train security forces and conduct counterterrorism operations against al Qaeda.
Obama has been insistent on legal protections.
If there is no immunity agreement, the United States might find itself in a similar situation as when it left Iraq. The refusal by the Iraqi government to extend legal protections for U.S. troops after the end of the war there was a major reason the United States left the country with no residual military training force.
There are currently some 66,000 U.S. troops in Afghanistan. The war there is the longest in American history.