Chicago (CNN) -- NATO leaders signed off Monday on President Barack Obama's exit strategy from Afghanistan that calls for an end to combat operations next year and the withdrawal of the U.S.-led international military force by the end of 2014.
Secretary General Anders Fogh Rasmussen told reporters at the conclusion of a two-day summit of the alliance leaders that the plan calls for handing over security responsibilities to Afghan forces in 2013, then withdrawing foreign forces the following year. After that, a new and different NATO mission will advise, train and assist the expected 350,000-strong Afghanistan force, Rasmussen said.
The plan is backed by Afghan President Hamid Karzai, who sat down Monday to speak exclusively with CNN's Wolf Blitzer.
"We have finalized plans so 2014 will be a year in which the United States will not be spending as much money in Afghanistan as it is spending today. It will save money and we will be providing security ourselves," he said. "That transition and the eventual withdrawal in 2014 of the U.S. forces and other NATO forces from Afghanistan is good for Afghanistan and good for our allied countries."
Obama said NATO leaders were leaving Chicago with "a clear road map" to bring the war in Afghanistan to a "responsible end."
"I don't think that there's ever going to be an optimal point where we say -- this is all done, this is perfect, this is just the way we wanted it and now we can wrap up all our equipment and go home. This is a process, and it's sometimes a messy process, just as it was in Iraq," he said.
The second day of their two-day summit focused on Afghanistan, with Karzai and the heads of other countries contributing to the U.S.-led International Security Assistance Force also in attendance.
Obama wanted NATO to commit to long-range support for Afghanistan, and Rasmussen said the alliance would support Afghan forces after the combat mission ends.
"Today we reaffirmed our strong commitment to support their training, equipping, financing and capability development in the years to come," Rasmussen said, adding it will be a "new mission with a new role for NATO," not "ISAF with a different name."
Rasmussen confirmed that some NATO members have agreed to contribute money for the $4 billion a year needed to help fund the Afghanistan security forces after the NATO mission ends, but said the summit was never intended to secure that funding.
While the Afghanistan force is expected to number 350,000 in 2014, Rasmussen said the size would likely decrease in future years depending on the security situation on the ground and other factors.
He also said he expected an agreement soon for Pakistan to reopen its border with Afghanistan to military shipments of departing NATO forces, which would resolve a sticky issue in planning the withdrawal of foreign forces.
"So far, the closure of the transit routes has not had a major impact on our operations," Rasmussen said, but added the transit routes were very important and that he expected their reopening "in the very near future."
Pakistan closed the ground routes after a NATO airstrike in November killed two dozen of its soldiers. NATO insists the incident was an accident. Obama offered his condolences but refused to apologize.
The United States and Pakistan have not come to an agreement on the price of reopening the supply lines, according to senior administration officials, who spoke on condition of anonymity because of the sensitivity of the issue.
Without a deal, officials said Obama would not meet with President Asif Ali Zardari at the summit. However, Obama and Zardari had a brief conversation Monday morning on the sidelines of the NATO session.
The United States and Pakistan are making "diligent progress" on the question of reopening the supply routes, the U.S. president said.
"Ultimately it is in our interest to see a successful, stable Pakistan and it is in Pakistan's interests to work with us and the world community to ensure that they themselves are not consumed by extremism that is in their midst," Obama told reporters.
When asked about turning over security responsibility to Afghan forces next year, Rasmussen denied it was an acceleration of the transition, saying the plan all along was to withdraw troops in 2014 after shifting the lead security role to Afghan forces.
"It has been within our road map right from the outset," he said.
Asked Monday by Blitzer whether Afghanistan will be ready by 2014 to assume full responsibility for the country's security, Karzai responded: "Absolutely."
"We've already worked out a plan to have in six months time 75% of the country taken over, with regard to security by the Afghan security forces ," he said.
Outside the NATO meeting, protesters marched and rallied on Monday, a day after violent clashes with police.
Obama thanked the city's mayor and its police force for their work, which he said was done under "significant pressure and a lot of scrutiny."
"This is part of what NATO defends -- is free speech and freedom of assembly," he said.
Earlier Monday, Obama told the dozens of heads of state in attendance that the goal is to "responsibly bring this war to an end" in the next 19 months.
He cited a recent strategic partnership agreement he signed with Karzai as a step toward ensuring that "as Afghans stand up, they will not stand alone."
Obama and Karzai, who met a day ahead of Monday's NATO talks on Afghanistan, both agreed that the end of the war was close.
Following their meeting, Obama said the transition of the NATO-led force from a combat role to one of support of Afghan forces paints "a vision post-2014 in which we have ended our combat role, the Afghan war as we understand it is over."
Karzai reiterated his commitment to the timetable, "so that Afghanistan is no longer a burden on the shoulder of our friends in the international community, on the shoulders of the United States and our other allies.
"Afghanistan, indeed, Mr. President, as you very rightly put it, is looking forward to an end to this war, and a transformational decade," he said.
CNN's Chelsea J. Carter, Adam Levine, Jessica Yellin and Tom Cohen contributed to this report.