There have been threats by some senior administration officials, including Susan E. Rice, the national security adviser, that a complete American withdrawal from Afghanistan — the so-called zero option — would be considered if Mr. Karzai did not sign the deal by the year’s end.  http://www.nytimes.com/2013/12/24/world/asia/us-softens-deadline-for-deal-to-keep-troops-in-afghanistan.html?ref=us&_r=0

Instead of prompting Mr. Karzai to action, however, setting a boundary appears to have only reinforced his sense that American officials will back down if he refuses their demands — a lesson that has been repeated often over the past 12 years.

“I don’t know if I would call it bluffing,” said one American official, who spoke on the condition of anonymity to discuss internal deliberations. “But it looks like that’s what we were doing, and now it looks like Karzai is calling us out.”

The official insisted that planning for a potentially final withdrawal in 2014 was still underway, and that it was still a very real possibility. “But if we want a deal,” the official continued, “we’re going to have to wait.”

The question now is how long the administration is willing to wait. American officials have been careful in recent interviews not to suggest any new deadlines. “I think it’s pretty obvious why,” one administration official said.

The officials spoke only in vague terms about timelines that stretched into the new year, and reiterated earlier statements about how the administration’s preferred outcome is to reach a deal that would permit a small American force, along with some European troops, to stay on to train and advise Afghan soldiers and the police.

Mr. Karzai, after initially agreeing to the wording of the security deal, known as a bilateral security agreement, or B.S.A., said he wanted to wait until after the April 2014 presidential elections before signing.

But American officials say they need a deal finalized soon, in part to give European allies, who lack the robust logistics capability of the United States military, time to plan for an extended mission in Afghanistan. They also said the longer they waited, the more likely those in the administration — and the public — who want a complete withdrawal would gain support.

“We’ve been clear that our preference is to conclude the B.S.A. by the end of the year, and that if we cannot conclude a B.S.A. promptly thereafter, then we will be forced to initiate planning for a post-2014 future in which there would be no U.S. or NATO troop presence in Afghanistan,” said Laura Magnuson, a spokeswoman for the White House. “That has not changed.”

With the deal in limbo, the official focus in Kabul has shifted to talks on a companion agreement that would allow other NATO members, such as Italy and Germany, to keep forces in Afghanistan after the alliance’s combat mission formally ends next year.

The NATO-led coalition here announced the start of talks in a statement this past weekend. The statement was carefully worded, Western officials said, to head off any talk from Mr. Karzai of cutting out the Americans and trying to work only with European allies, an idea he has previously floated in meetings with Western officials.

Mr. Karzai appears to still be holding out for a better deal with the United States, despite the original accord’s endorsement last month by a grand council of Afghans, known as a loya jirga, and economic signs that public confidence is falling in the absence of an agreement.

“I want this security agreement with the U.S.,” a statement from the presidential palace quoted Mr. Karzai as saying in an off-the-record meeting with Afghan journalists on Sunday. “But Afghans’ homes should be protected from American operations, and Afghanistan should not become the battleground of a continuous war.”

Mr. Karzai reiterated that a formal peace process with the Taliban must begin before he signs, and that the United States commit itself to Afghanistan’s peace and security.

“The conditions that we have put forward for the signing of the security agreement are ridding Afghanistan of instability and war,” Mr. Karzai told the journalists.

He would sign, he said, “as soon as they are ready to accept our conditions, because we are not in a rush.”

“I think if you want to explain what’s going on, you have to look at why it’s confusing,” an official said. “We’ve never spoken with one voice. One person says sign now, another tells Karzai that he has time. It’s not been clear what’s going on.”