KABUL, Afghanistan — Contact between the Taliban, the United States and other western officials over potential peace negotiations to end the war appears to have been severed completely in recent weeks, after the name of the reported Taliban negotiator involved in the talks was leaked to the international press in June.

Tayyab Agha, a long-time confidante of Taliban spiritual leader Mullah Omar, is reportedly missing following the revelation he met with U.S. officials in Germany and Qatar in March and April in a bid to jump-start peace talks.

The United States, seeking to extricate itself from an increasingly violent conflict, has been pushing for about a year to bring Taliban leaders to the bargaining table.

After Afghan President Hamid Karzai and U.S. President Barack Obama confirmed that talks with the Taliban had begun earlier this year, Tayyab Agha, observers say, became America’s best shot at coaxing insurgents into a dialogue.

“We can confirm that there is a problem reaching Tayyab Agha right now,” a member of Afghanistan’s High Peace Council and former member of the Taliban, Hajji Musa Hotak, told GlobalPost. Karzai established the 70-member High Peace Council in 2010 to kick-start and oversee Afghan government talks with the Taliban.

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Agha, a young but trusted emissary of the Taliban leadership and who lives in Pakistan, was tapped early on as a Taliban front man for his apt foreign language skills and literacy in world affairs.

“I was told that after returning to Pakistan from his meetings with officials in Germany, Agha was threatened by the Pakistani government,” Hotak said. “Since then, there has been no address for him. He either wants to hide, or Pakistan wants him to be unavailable to the Americans.”

Pakistan, which nurtured the Taliban in their early years partly due to sympathy for the movement among conservative Muslims in the country’s intelligence service, also sees the Taliban as a way to ensure Pakistani influence in Kabul at the expense of its arch-rival India.

Many say Pakistan is worried it will lose its strategic grip on Afghanistan with any peace talks that do not include Pakistani leadership.

While Hotak’s allegations of threats made against Agha by the Pakistani government could not be confirmed, it is widely known that Pakistan wields considerable influence over the Taliban leadership, which is based in the Pakistani cities of Karachi, Peshawar and Quetta.

The Taliban’s former military chief, Mullah Abdul Ghani Baradar, was arrested by Pakistan’s Inter-Services Intelligence (ISI) in Pakistan in March 2010, just weeks after he was reported to have reached out to the Afghan government in a reconciliation effort.

“From the Taliban side, there might be high-level people who are willing to reconcile, but they are afraid to say it,” another peace council member, and former member of parliament, Hashim Fulad, said.

“They are afraid after what happened to Mullah Barardar,” he continued. “When he started to have direct connections with Afghan government, he was arrested. They are under pressure.”

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But even without Pakistan’s meddling, the process has so far borne little fruit at the diplomatic level, observers and those involved in helping initiate peace talks say.

Plagued by an imposter negotiator in one case — when foreign troops doled out cash to a Peshawar shopkeeper who posed as a Taliban figure last fall — and missed opportunities over a decade, the process provokes little faith among Afghans.

In the meantime, violence is on the rise. More civilians have died in the first six months of 2011 than at any other time during the 10-year-old Afghan conflict, the United Nations says.

And while insurgents are still out-gunned by U.S.-led NATO troops, they have recently pulled off a series of spectacular attacks, including high-profile assassinations and the downing of a U.S. helicopter last week, that have undermined U.S. claims of progress.

“We still do not have a single achievement through our efforts with the peace council so far,” Hotak said. “I am a member of the committee responsible for initiating contact, and we still do not have contact with Taliban leaders through official channels.”

Hotak blames High Peace Council Chief Burhanuddin Rabbani for the lack of progress, charging that the former president and once virulent anti-Taliban commander opposes bringing Taliban leaders to the table as a unified group.

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If they are instead fragmented by the process, and reconciled one-by-one, Hotak says, the Taliban will be too weak to call for any power-sharing agreement.

Still, Fulad says Taliban leaders, through intermediaries, have been adamant about their demands for the start of negotiations.

“Even though they are not telling us directly, because we are not in official contact with them, their demands are clear,” Fulad said. “They want the withdrawal of foreign forces.”

For their part, the U.S. and Afghan governments say the Taliban must renounce Al Qaeda, lay down their arms and accept the Afghan constitution.

Fulad says both parties should agree upon the constitution once talks are underway. Many Afghans are worried the Taliban will seek provisions that prohibit women from attending school or working outside the home.

“If the Taliban sit with us, and they say they want to change the constitution, anything is possible,” Fulad said. “The constitution was made by the people, and it can be changed by the people, too.”