NATO defense ministers endorsed a plan Friday to hand over responsibility for security in three cities, two provinces and much of the capital to Afghan forces over the next several months, commencing the critical first step in a transition to full Afghan control by the end of 2014.

But Defense Secretary Robert M. Gates pointedly urged other members of the alliance not to use the milestone as a reason to withdraw their forces. Despite President Obama’s commitment to begin drawing down U.S. troops this summer, Gates implored his fellow defense chiefs to maintain their commitments to stabilizing Afghanistan, and he rebuked them for focusing too much on their departure from the war-torn nation instead of displaying “unity and commitment.”

“Frankly, there is too much talk about leaving and not enough talk about getting the job done right,” Gates said at NATO headquarters in Brussels. “Too much discussion of exit and not enough discussion about continuing the fight. Too much concern about when and how many troops might redeploy, and not enough about what needs to be done before they leave.”

There are few U.S. forces in first six areas slated to be transferred. Gates and other senior U.S. officials want the nations that have troops in those places to redeploy them to other parts of the country, or to contribute them to a multinational effort to train Afghan security forces, although most of those nations have not yet made firm commitments to do so.

“As the Afghan security forces take an increasing responsibility . . . this transition dividend will be reinvested in other areas as required,” NATO Secretary General Anders Fogh Rasmussen said at a news conference. He sought to assuage Gates’s concerns by pledging that as NATO’s engagement in Afghanistan evolves, “We are not heading for the exit. We have committed to a long-term partnership with the Afghan government and its people.”

But Rasmussen also acknowledged the alliance’s limitations in getting member-states to share that view. “Of course, ultimate decisions on the redeployment and reinvestment of forces remain a national responsibility,” he noted.

The six areas include all but one district in Kabul province, which is the responsibility of Turkish forces. The list also includes the provinces of Bamiyan and Panjshir, both of which have been largely free of violence for years and are home to few foreign troops.

The three cities are Herat in the west (currently the responsibility of Italian forces), Mazar-e Sharif in the north (Germany) and Lashkar Gah in the southwest (Britain). Lashkar Gar is the capital of Helmand, the country’s most violent province, but the city itself has been relatively peaceful.

The list of places to be transferred was not released by NATO because it wants Afghan President Hamid Karzai to make the official announcement on March 21, during a speech marking the Afghan new year. The six areas were first reported by the Associated Press and later confirmed by two senior U.S. military officials.

The areas were approved by a joint Afghan-NATO transition board but the list still requires formal authorization from Karzai’s government, Rasmussen said.

“There is still, of course, much hard work to do to ensure that transition is successful and irreversible,” he said.

Gates said the U.S. drawdown that begins this summer “will not sacrifice the significant gains made to date, or the lives lost, for a political gesture.” He bluntly told his fellow defense chiefs that “in return, we expect the same from your nations.”

“Let me be clear: uncoordinated national drawdowns would risk the gains made to date,” he said. “Considerations about any drawdown of forces must be driven by security conditions and . . . operational needs, and not by mathematical calculation shaped by political concern.”

Gates emphasized that the United States plans to spend $120 billion this year on the war and now has almost 100,000 troops in Afghanistan-- more than double all of the other NATO members combined. He also noted that the U.S. military suffered more casualties in 2010 than in any previous year of the conflict.

“These are the tragic costs of success,” he said.