NATO chief Fogh Anders Rasmussen said Tuesday the alliance is preparing plans for a complete withdrawal from Afghanistan if Kabul does not ratify a postwar plan with the United States.
The so-called zero option for NATO forces in Afghanistan is one of several postwar scenarios being hashed out during the alliance's annual meeting in Brussels this week.
Without a plan, known inside the Pentagon as a Bilateral Security Agreement (BSA), "there can be no deployment and the planned [NATO] assistance will be put at risk," Rasmussen told reporters at NATO's headquarters.
"It is my firm hope and intention therefore to continue our efforts to support Afghanistan, once these agreements are concluded," he added.
Rasmussen's comments come a day after the Pentagon announced the U.S. and Afghanistan have until late February or early March to reach a deal on a security agreement, or risk having no American troops in the country after 2014.
On Monday, Pentagon said it had some flexibility on the deadline for a final deal.
“Dec. 31 is not a hard and fast date,” Defense Department spokesman Col. Steve Warren said.
But the Pentagon is adamant that time is running out for Karzai to approve the pact.
“We would like to see [it] signed as quickly as possible,” Warren said.
The deal is supposed to lay the groundwork for a postwar U.S. military presence after the 2014 deadline for the withdrawal of U.S. troops.
A BSA must be in place with the United States before Washington and NATO can ink a follow-on security deal with the alliance, known as a status of forces agreement. Then a final agreement on troop numbers needs to be reached.
The U.S. wants to get the initial BSA deal done to begin work on the subsequent accords.
The White House is considering a 9,000- to 10,000-man postwar force in Afghanistan, as part of 15,000-man NATO force tasked with training and counterterrorism missions.
The Loya Jirga, a collection of key Afghan tribal leaders overwhelmingly approved the BSA in October.
Karzai has repeatedly delayed approval, demanding Washington accede to a number of conditions.
Those demands prompted Obama to consider abandoning the postwar pact and pulling all American troops from Afghanistan.