WASHINGTON: President Barack Obama and Afghan President Hamid Karzai met Friday at the White House to discuss the future of the U.S. role in Afghanistan and the 66,000 American troops in harm's way.

The two leaders planned a joint news conference following a private Oval Office meeting and working lunch. White House officials said, however, that Obama would not announce any decisions on the next phase of troop withdrawals or whether any U.S. forces would stay behind in Afghanistan after the war formally ends in 2014.

U.S. commanders in Afghanistan have proposed keeping 6,000 to 15,000 U.S. troops after 2014 to continuing pursuing terrorists and training Afghan security forces. But the White House, which tends to favor lower troop levels than the generals do, says Obama would be open to pulling all U.S. forces out of Afghanistan at the end of 2014.

"We wouldn't rule out any option," said Ben Rhodes, Obama's deputy national security adviser. "We're not guided by the goal of a certain number of U.S. troops in the country. We're guided by the objectives that the president set - disrupt, dismantle, defeat al-Qaida."

Beyond troop levels, Obama and Karzai were also expected to discuss preparations for next year's Afghan elections and the prospects for advancing Afghan peace talks with the Taliban.

Friday's meeting was the first between Obama and Karzai since November's U.S. presidential election. Heading into his second term, Obama is shaking up his national security team, including key players who deal with Karzai and the war.

Secretary of State Hillary Rodham Clinton and Defense Secretary Leon Panetta are both expected to leave their posts within weeks. The president nominated Sen. John Kerry, a Democrat, as the nation's top diplomat and former Sen. Chuck Hagel, a Republican, to lead the Pentagon.

Both Kerry and Hagel are likely to favor a more rapid withdrawal of U.S. forces.

After Karzai met Thursday with Clinton and Panetta, the Pentagon chief offered an upbeat assessment of the war's progress.

"After a long and difficult path, we finally are, I believe, at the last chapter of establishing an Afghanistan, a sovereign Afghanistan, that can govern and secure itself for the future," Panetta said.

The U.S.-led NATO coalition is aiming to turn all combat missions over to Afghan forces by the end of this year. The 66,000 U.S. forces still there are already turning over territory or handing off many combat missions to the Afghans.

Still, the war's endgame is punctuated with uncertainty, beginning with doubts about whether the Afghan government can build legitimacy by credibly serving its population. Also in question is whether Afghan security forces will be capable of holding off the Taliban after international forces leave.

Panetta told a news conference that he and Karzai had laid the groundwork for the Afghan leader's White House meeting.

"We made very good progress on, you know, the kind of equipment that we would try to make available to them," to enable the Afghans to not only secure their borders but also prevent a Taliban takeover, Panetta said.

Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told the same news conference that U.S. and Afghan officials are developing a common assessment of threats Afghanistan is likely to face in the future. Conclusions from that study will help determine the full range of Afghanistan's military requirements, he said.

Karzai was greeted at the Pentagon by a ceremonial honor guard, and at a photo-taking session in Panetta's office, the Afghan leader said he could assure the American people that his country "will not ever again be threatened by terrorists from across our borders" - an allusion to the al-Qaida leaders hiding in Pakistan. It was from Afghanistan that Osama bin Laden and his al-Qaida operatives plotted the Sept. 11, 2001, attacks on the United States.