An Air Force technician works on preflight checks for a Global Hawk drone at an undisclosed base in Southwest Asia, Nov. 23, 2010.

WASHINGTON — The Obama administration is making contingency plans to use air bases in Central Asia to conduct drone missile attacks in northwest Pakistan in case the White House is forced to withdraw all U.S. forces from Afghanistan at the end of this year, according to U.S. officials.

But even if alternative bases are secured, the officials said, the CIA’s capability to gather sufficient intelligence to find al-Qaida operatives and quickly launch drone missiles at specific targets in Pakistan’s mountainous tribal region will be greatly diminished if the spy agency loses its drone bases in Afghanistan.

The CIA’s targeted killing program thus may prove a casualty of the bitter standoff with Afghan President Hamid Karzai over whether any U.S. troops can remain in Afghanistan after 2014, as the White House has sought. Karzai has refused to sign a bilateral security agreement to permit a long-term American deployment, and some White House aides are arguing for a complete pullout.

According to current and former officers, CIA analysts operating from fortified outposts near the Pakistani border evaluate electronic intelligence, while case officers meet sources who help them identify targets. They pay people to place GPS trackers on cars or buildings to help guide the drone-launched missiles.

“There is an enormous amount of human intelligence collected that supports the strikes, and those bases are a key part of it,” one official said.

The CIA cannot fly drones from its Afghan drone bases without U.S. military protection, according to several American officials who spoke on condition of anonymity because the program is classified. If the bases are evacuated, the CIA fleet of armed Predator and Reaper drones could be moved to air fields north of Afghanistan, U.S. officials say, without naming the countries.

“There are contingency plans for alternatives in the north,” said one official briefed on the matter.

Defense Secretary Chuck Hagel publicly acknowledged for the first time this month that U.S. officials are examining different basing options for drones.

“I don’t get into the specifics of what our plans are on intelligence and drone strikes,” he said at a news conference. “You’re constantly updating and changing ... where you posture those assets, where the threats are most significant, where do you have allies that are willing to work with you.”

The CIA and the military used an air base in Uzbekistan to conduct drone flights until the U.S. was evicted in 2005, said Brian Glyn Williams, a University of Massachusetts professor and author of the book, “Predators: The CIA’s Drone War on Al Qaeda.”

The military also has used a base in Kyrgyzstan to conduct air operations, including moving troops and supplies into Afghanistan. The Pentagon announced last fall that it would shift those operations to Romania this summer.

Last month, Maj. Gen. Michael K. Nagata, commander of U.S. special operations in the Middle East and Central Asia, visited Tajikistan, which abuts Afghanistan’s northern border, for talks on “issues of bilateral security cooperation” and “continued military cooperation,” according to a U.S. Embassy statement in Dushanbe, the capital.

American officials refused to say whether they are seeking permission to base CIA drones in Tajikistan, which permits the U.S. to ship military equipment and supplies through its territory. Several officials said Russia almost certainly would try to block any new U.S. basing agreement in Central Asia. Moscow long has sought to deny Washington more of a foothold in the region.

Officials say a new jet-powered drone, called the Predator C, or Avenger, could figure in plans to use bases outside Afghanistan. The Avenger could “get to ‘hot’ targets in Pakistan much faster and might solve some of these logistic problems posed by the slower-moving, propeller-driven Predator and Reaper drones,” said Williams, the professor.

General Atomics, which makes the Avenger, says it is ready for combat. So far, the San Diego-based company has built four prototypes.

Drone strikes in Pakistan have grown less frequent — 28 last year, down from 117 in 2010 — and more precise. The London-based Bureau of Investigative Journalism, which has compiled a database of known drone strikes, found four noncombatants killed in 2013.

But the ability to act quickly, without harming civilians, would suffer if the CIA was forced to leave the area, officials say.

“People think of drones as if they fly to a place, shoot and go home,” said a former U.S. official familiar with counter-terrorism operations. “But there is a large amount of coordination and intelligence gathering that takes place, and it takes a lot of time and patience.”

Another challenge for counterterrorism planners is President Barack Obama’s stated intention to gradually shift responsibility for drone attacks from the CIA to the military. The Pentagon’s Joint Special Operations Command conducts drone strikes in Yemen and Somalia under a different legal standard than the CIA uses in Pakistan.

Outside a war zone, the military normally requires an invitation from the host country. The CIA drone campaign is covert. Pakistan consents through back channels, while formally protesting the strikes in diplomatic forums and at the United Nations. That arrangement could pose a legal problem if the U.S. military takes over drone strikes, officials say.

In any case, Congress has balked at handing CIA drone strikes to the military. Key lawmakers favor keeping the CIA program active, especially for Pakistan. “They don’t think we’re as precise as the CIA and (worry) that the program would become more transparent if we took over,” a senior Defense official said.

Intelligence officials back a plan by Gen. Joe Dunford, the top commander in Afghanistan, for keeping roughly 10,000 U.S. troops in the country after 2014, if only to keep the CIA drone program going.

“It’s one of the reason the intelligence community is supporting Gen. Dunford’s plan,” one official said.

Obama has not yet approved a deployment plan, in part because of the standoff with Karzai.