"The keys are to keep expectations low, to remember that a compromise is unlikely because no one can say what it would consist of," said Michael O'Hanlon of the Brookings Institution. He added that in his opinion, the Taliban wrongly "expect to win the war once NATO is largely gone come 2015."
"All that said, it's a potentially useful step if we don't confuse ourselves or wind up in polarizing debates within the coalition," O'Hanlon said.
In Doha, Ali Bin Fahad Al-Hajri, the assistant to the foreign minister of Qatar, said the Emir of the Gulf state had given the go-ahead for the office to open.
"Negotiations are the only way for peace in Afghanistan," Al-Hajri said.
Taliban spokesman Mohammad Naim said the Islamic Emirate of Afghanistan, as the Taliban were known when they ruled the country, was willing to use all legal means to end what they called the occupation of Afghanistan. But he did not say they would immediately stop fighting.
"The jihad continues to end the occupation and establish an Islamic emirate. To achieve this goal, we will follow every legitimate means," he said. "The emirate of the Taliban, with its military effort, has a strategic goal related to the future of Afghanistan. The movement is not intending to harm any other parties and will not allow anybody to use Afghan territory to threaten other countries."
The Obama administration officials said the U.S. and Taliban representatives will hold bilateral meetings. Karzai's High Peace Council is expected to follow up with its own talks with the Taliban a few days later.
But in making their announcement in Doha, the Taliban did not specifically mention talks with Karzai or his representatives.
"We don't recognize the Afghan government and the government of Karzai. The talks will be with the Americans only in Doha under the patronage of Qatar," he said. "We represent the people of Afghanistan. We don't represent the Karzai government."
The administration officials acknowledged the process will be "complex, long and messy" because of the ongoing level of distrust between the parties.
The officials, who spoke on condition of anonymity because they were not authorized to speak on the record, vowed to continue to push the Taliban further, saying that the Taliban ultimately must also break ties with al-Qaida, end violence and accept Afghanistan's constitution -- including protections for women and minorities.
They said the U.S. had long demanded that the Taliban make a statement distancing the group from international terrorism, but had said that they did not expect them to break ties with al-Qaida immediately. That would be one of the outcomes of the negotiating process, they added.
The U.S. will hold its first formal meetings with the Taliban in Doha within a few days, senior officials said, with the expectation that it will be followed up days later by a meeting between representatives of the Taliban and the High Peace Council. The first meeting will focus on an exchange of agendas and consultations on next steps.
Naim did not give a schedule for talks.
The Taliban office is in one of the diplomatic areas in Doha. Its sign reads: "The Political Bureau of the Islamic Emirate of Afghanistan in Doha."
Despite Karzai's stated hope that the process will move almost immediately to Afghanistan, U.S. officials do not expect that to be possible in the near future.
The Taliban have for years refused to speak to the government or the High Peace Council, set up by Karzai three years ago, because they considered them to be U.S. "puppets." Taliban representatives have instead talked to American and other Western officials in Doha and other places, mostly in Europe.
Officials said Obama was personally involved in working with Karzai to enable the opening of the office, and that Kerry had also played a major role. Obama briefed other leaders at the summit meeting, which included the countries of Britain, Russia, Germany, Japan, Canada, France and Italy.
James Dobbins, the U.S. special representative for Afghanistan and Pakistan, was scheduled to leave Washington on Tuesday to visit Turkey, Qatar, Afghanistan and Pakistan, focusing primarily on "reconciliation efforts," according to State Department spokeswoman Jen Psaki.