Kabul:
For months, the secret talks unfolding between Taliban and Afghan leaders to end the war appeared to be showing promise, if only because of the repeated appearance of a certain insurgent leader at one end of the table: Mullah Akhtar Muhammad Mansour, one of the most senior commanders in the Taliban movement.
But now, it turns out, Mr. Mansour was apparently not Mr. Mansour at all. In an episode that could have been lifted from a spy novel, United States and Afghan officials now say the Afghan man was an impostor, and high-level discussions conducted with the assistance of NATO appear to have achieved little.
"It's not him," said a Western diplomat in Kabul intimately involved in the discussions. "And we gave him a lot of money."
American officials confirmed Monday that they had given up hope that the Afghan was Mr. Mansour, or even a member of the Taliban leadership.
NATO and Afghan officials said they held three meetings with the man, who traveled from across the border in Pakistan, where Taliban leaders have taken refuge.
The fake Taliban leader even met with President Hamid Karzai, having been flown to Kabul on a NATO aircraft and ushered into the presidential palace, officials said.
The episode underscores the uncertain and even bizarre nature of the atmosphere in which Afghan and American leaders search for ways to bring the nine-year-old American-led war to an end. The leaders of the Taliban are believed to be hiding in Pakistan, possibly with the assistance of the Pakistani government, which receives billions of dollars in American aid.
Many in the Taliban leadership, which is largely made up of barely literate clerics from the countryside, had not been seen in person by American, NATO or Afghan officials.
Doubts were raised about the man claiming to be Mullah Mansour -- who by some accounts is the second-ranking official in the Taliban, behind only the founder, Mullah Mohammed Omar -- after the third meeting, held in the southern Afghan city of Kandahar. A man who had known Mr. Mansour years ago told Afghan officials that the man at the table did not resemble him. "He said he didn't recognize him," said an Afghan leader, who spoke on the condition of anonymity.
The Western diplomat said the Afghan man was initially given a sizable sum of money to take part in the talks -- and to help persuade him to return.
While the Afghan official said he still harbored hopes that the man would return for another round of talks, American and other Western officials said they had concluded that the man in question was not Mr. Mansour. Just how the Americans reached such a definitive conclusion -- whether, for instance, they were able to positively establish his identity through fingerprints or some other means -- is unknown.
As recently as last month, American and Afghan officials held high hopes for the talks. Senior American officials, including Gen. David H. Petraeus, said the talks indicated that Taliban leaders, whose rank-and-file fighters are under extraordinary pressure from the American-led offensive, were at least willing to discuss an end to the war.
The American officials said they and officials of other NATO governments were helping to facilitate the discussions, by providing air transport and securing roadways for Taliban leaders coming from Pakistan.
Last month, White House officials asked The New York Times to withhold Mr. Mansour's name from an article about the peace talks, expressing concern that the talks would be jeopardized -- and Mr. Mansour's life put at risk -- if his involvement were publicized. The Times agreed to withhold Mr. Mansour's name, along with the names of two other Taliban leaders said to be involved in the discussions. The status of the other two Taliban leaders said to be involved is not clear.
Since the last round of discussions, which took place within the past few weeks, Afghan and American officials have been puzzling over who the man was. Some Afghans say the man may have been a Taliban agent sent to impersonate Mr. Mansour. "The Taliban are cleverer than the Americans and our own intelligence service," said a senior Afghan official who is familiar with the case. "They are playing games."
Others suspect that the fake Taliban leader, whose real identity is not known, may have been dispatched by the Pakistani intelligence service, known by its initials, the ISI. Elements within the ISI have long played a "double-game" in Afghanistan, reassuring United States officials that they are actively pursuing the Taliban while at the same time providing support for the insurgents.
Publicly, at least, the Taliban leadership is sticking to the line that there are no talks at all. In a recent message to his followers, Mullah Omar denied that there were any talks unfolding at any level.
"The cunning enemy which has occupied our country, is trying, on the one hand, to expand its military operations on the basis of its double-standard policy and, on the other hand, wants to throw dust into the eyes of the people by spreading the rumors of negotiation," his message said.
Despite such statements, some senior leaders of the Taliban did show a willingness to talk peace with representatives of the Afghan government as recently as January.
At that time, Abdul Ghani Baradar, then the deputy commander of the Taliban, was arrested in a joint C.I.A.-ISI raid in the Pakistani port city of Karachi. Although officials from both countries hailed the arrest as a hallmark of American-Pakistani cooperation, Pakistani officials have since indicated that they orchestrated Mr. Baradar's arrest because he was engaging in peace discussions without the ISI's permission.
Afghan leaders have confirmed this account.
Neither American nor Afghan leaders confronted the fake Mullah Mansour with their doubts about his identity. Indeed, some Afghan leaders are still holding out hopes that the man really is or at least represents Mr. Mansour -- and that he will come back soon.
"Questions have been raised about him, but it's still possible that it's him," said the Afghan leader who declined to be identified.
The Afghan leader said negotiators had urged the man claiming to be Mr. Mansour to return with colleagues, including other high-level Taliban leaders whose identities they might also be able to verify.
The meetings were arranged by an Afghan middleman with ties to both the Afghan government and the Taliban, officials said.
The Afghan leader said both the Americans and the Afghan leadership were initially cautious of the Afghan man's identity and motives. But after the first meeting, both were reasonably satisfied that the man they were talking to was Mr. Mansour. Several steps were taken to establish the man's real identity; after the first meeting, photos of him were shown to Taliban detainees who were believed to know Mr. Mansour. They signed off, the Afghan leader said.
Whatever the Afghan man's identity, the talks that unfolded between the Americans and the man claiming to be Mr. Mansour seemed substantive, the Afghan leader said. The man claiming to be representing the Taliban laid down several surprisingly moderate conditions for a peace settlement: that the Taliban leadership be allowed to safely return to Afghanistan, that Taliban soldiers be offered jobs, and that prisoners be released.
The Afghan man did not demand, as the Taliban have in the past, a withdrawal of foreign forces or a Taliban share of the government.
Sayed Amir Muhammad Agha, a onetime Taliban commander who says he has left the Taliban but who acted as a go-between with the movement in the past, said in an interview that he did not know the tale of the impostor.
But he said the Taliban leadership had given no indications of a willingness to enter talks.
"Someone like me could come forward and say, 'I am a Talib and a powerful person,' " he said. "But I can tell you, nothing is going on."
"Whenever I talk to the Taliban, they never accept peace and they want to keep on fighting," he said. "They are not tired."