A Western official said Mr. Sarkozy’s threat could lay bare “real cracks in the coalition” at a time when the alliance is seeking a cohesive position to assure the Afghan government of its long-term commitment and to push the Taliban insurgents to negotiate a peace deal rather than continue fighting.
It was the second fatal attack in a month involving an Afghan soldier opening fire on French troops and came at a time when American forces are deeply concerned about increasing numbers of killings of American and other allied forces by the Afghan soldiers they fight alongside and train. It also comes as many European countries with troops here are facing unprecedented economic pressures at home and adds to public questioning of the value of continued involvement in Afghanistan.
If France, the fourth-largest troop-contributing country after the United States, Britain and Germany, were to reduce its numbers more than planned it could spur other countries to follow suit, leaving the Afghans feeling less secure, said Western and Afghan officials.
President Hamid Karzai quickly expressed his condolences in a strong statement that reminded the French of their long involvement with Afghanistan and conveyed the Afghan people’s gratitude.
“Throughout history, the two countries have enjoyed a sincere relationship, which Afghan people will always cherish,” Mr. Karzai said.
The four French service members were killed and a number more wounded on Friday when a gunman wearing an Afghan National Army uniform turned his weapon on them, according to an Afghan police official in Kapisa Province in eastern Afghanistan where the episode occurred and a Western official in Kabul, who spoke on condition of anonymity because he was not authorized to speak to the press. The Afghan police official, Asadullah Hamidi, said the shooting happened in the southern part of Tagab District, an area that is viewed as dangerous and dominated by insurgent forces.
The gunman is in custody, a NATO official said.
The attack prompted Mr. Sarkozy to tell French diplomats at an annual meeting in Paris on Friday that he had ordered the suspension of training and combat operations by French forces in Afghanistan.
“If security conditions are not established clearly, then the question of an early return of the French Army will be asked,” he said. He added: “It is a difficult decision that we will have to take in the coming days.”
But, he went on, the decision was one he felt he had to make “for the French people and our soldiers.” Much of Mr. Sarkozy’s public behavior at present is perceived by analysts through the prism of presidential elections beginning in April, and he can ill afford to be depicted as anything less than robust and decisive in defending French interests.
While he has not yet announced his candidacy, the French leader is facing a tough re-election battle against a challenge from the opposition Socialists, who have already promised an early withdrawal of French troops from Afghanistan by the spring of 2013.
Western officials in Kabul said they were not altogether surprised by Mr. Sarkozy’s mention of an early withdrawal. President Karzai is set to visit Paris next to meet Mr. Sarkozy and, in military circles here it was expected that the French leader would use the encounter to announce a larger troop withdrawal than many other contributor nations in the NATO alliance wanted.
The French contingent of some 3,600 soldiers is vastly outnumbered by the dominant American military presence, but its withdrawal would present a damaging psychological blow to the alliance and would be presented by the Taliban insurgents as a significant victory.
NATO is struggling to persuade major contributor nations not only to hew to their promise to remain in Afghanistan until the end of 2014, but also to commit to helping the country militarily after that date.
“It’s not very good in terms of alliance cohesion,” said a Western official in Kabul, speaking on condition of anonymity because he was not authorized to speak to the press. “If your fourth largest troop contributing country decides to pack up and go home, well that shows there are real cracks in the coalition.”
The bulk of the French contingent is based in troubled eastern Afghanistan, primarily in Kapisa Province and neighboring Sarobi, a district of Kabul Province. Although the area is close to Kabul it is heavily infiltrated by insurgents, and French soldiers have faced a number of lethal attacks, including an ambush in 2008 that killed 10 members of a parachute regiment as they moved through a narrow mountain pass and another in July 2011 when five members of a parachute regiment who had just met with local village elders were attacked by a suicide bomber.
Of non-American forces contributing to the alliance, only the British and the Germans have more troops on the ground.
Like other allied forces, French troops had been scheduled to withdraw from Afghanistan by the end of 2014.
Mr. Sarkozy said he would send his defense minister, Gérard Longuet, and the head of the armed forces, Adm. Edouard Guillaud, to Afghanistan and “until then all training operations and combat help from the French forces are suspended.”
“The French Army is at the side of its allies, but we cannot accept that a single one of our soldiers be killed or wounded by our allies,” Mr. Sarkozy said. “It is unacceptable. I will not accept it.”
The killing of the French soldiers raised the tally for a particularly bloody 24 hours for allied forces after a helicopter crashed late on Thursday, killing six more members of the international force.
The French have lost 82 soldiers including Friday’s casualties, according to icasualties.org, a Web site that tracks coalition deaths.