WASHINGTON -- The Obama administration, in a move aimed at reviving Afghan peace talks, has sweetened a proposed deal under which it would transfer Taliban detainees from Guantanamo Bay prison in exchange for a U.S. soldier held by Taliban allies in Pakistan.

The revised proposal, a concession from an earlier U.S. offer, would alter the sequence of the move of five senior Taliban figures held for years at the U.S. military prison to the Gulf state of Qatar, sources familiar with the issue said.

U.S. officials have hoped the prisoner exchange, proposed as a good-faith move in initial discussions between U.S. negotiators and Taliban officials, would open the door to peace talks between militants and the government of Afghan President Hamid Karzai.

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The revised proposal would send all five Taliban prisoners to Qatar first, said sources who spoke on condition of anonymity. Only then would the Taliban be required to release Sergeant Bowe Bergdahl, the only U.S. prisoner of war.

'Frustrated': Dad of Taliban prisoner Bowe Bergdahl takes matters into own hands

Previously, U.S. officials had proposed dividing the Taliban prisoners into two groups, and requiring Bergdahl's release as a good-faith gesture to come before the second group of prisoners would be moved out of Guantanamo.

Bergdahl, now 26 years old, disappeared from his base in southern Afghanistan in June 2009 and is believed to be being held by Taliban militants in northwestern Pakistan.

The White House and the Bergdahl family declined to comment on the revised proposal for a deal.

The altered transfer plans were discussed with Qatari officials during a visit in mid-June by Marc Grossman, President Barack Obama's special representative for Afghanistan and Pakistan, the sources said. It was unclear if the altered proposal had been put forward before those discussions.

Qatar, which is hosting a number of Taliban officials, has played a key role in almost two years of initial, secret discussions between U.S. officials and representatives of the shadowy militant group, which remains a formidable enemy in Afghanistan even as U.S. and NATO troops begin to withdraw.

As part of a process the Obama administration hoped would lead to substantive talks on Afghanistan's future, the Taliban's leadership had planned to formally open a political office in Doha. But the Taliban announced in March it would withdraw from the talks, citing what it said were inconsistencies in the U.S. negotiating position.

U.S. officials are now cautiously seeking to prepare the ground for a resumption in talks. But any negotiations involving the Taliban, even preliminary ones, could pose a political risk for Obama months before the U.S. presidential election.

The proposed prisoner transfer was first reported in December by Reuters.

Necessary evil?
The Taliban detainees are seen as among the most dangerous remaining at Guantanamo, and the transfer idea drew strong opposition on Capitol Hill even before it was formally proposed.

Many lawmakers fretted that transferred detainees would reappear on the battlefield, and objected to the possible release of prisoners blamed for bloody crimes in Afghanistan.

U.S. officials stress that the transfer, if it occurs, will be done in accordance with U.S. law, which requires Congress to be notified before any detainees are moved from Guantanamo.

The transfer of the prisoners has long been seen as a necessary evil by U.S. negotiators in their effort to coax the Taliban into talks.

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The militant group has long demanded their release, but the Pentagon, which handles detainee transfers, is particularly skeptical of a move officials there fear might not only fail to bring the Taliban to the negotiating table but also lead to the department being blamed for moving dangerous militants out of prison.

According to a report released early this year from the House Armed Services Committee, more than one in four of the 600 former detainees moved from Guantanamo to countries like Afghanistan, Saudi Arabia, or Yemen were confirmed or suspected to subsequently be engaged in 'terrorist activities.'

Democrats accused the committee's majority Republicans of fear-mongering when they released that report.

Of the five senior Taliban figures, many officials and lawmakers are particularly nervous about transferring Mullah Mohammed Fazl, a "high-risk detainee" who was in the first group sent to Guantanamo in early 2002, under what could be only loose security and travel restrictions.

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A former Taliban deputy minister of defense, Fazl is alleged to be responsible for the massacre of thousands of minority Shiites.

The group also includes Noorullah Noori, a former top military commander; former deputy intelligence minister Abdul Haq Wasiq; and Khairullah Khairkhwa, a former interior minister.

The identity of the fifth detainee remains unclear.

While a debate continues to rage within the U.S. administration about the wisdom of peace talks with the Taliban, Afghanistan experts see few other options for achieving even a modicum of stability in a region plagued by civil conflict for decades.

The Taliban may have been weakened by Obama's 2009-2010 troop surge into Afghanistan, but it remains a potent enemy as the foreign force grows smaller. It is also deeply mistrustful of U.S. overtures and has appeared this year to grapple with its own divisions.

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In early 2012, Western officials say, the Taliban's reclusive leaders struggled to contain a backlash from mid-level militants who opposed talking to the West. While they appear to have mostly succeeded in containing that response, even a start to real peace talks could still be years away.

Even so, analysts say there are signs that the Taliban leadership, based in Pakistan, may now be more open to a negotiated settlement, and these have included the appearance of a senior Taliban figure at a recent conference in Japan.

"The Taliban doesn't want a vacuum in Afghanistan or a civil war with the North they know they can't win," said Ahmed Rashid, a prominent Pakistani author and expert on the Taliban, referring to powerful northern warlords who battled the Taliban in the 1990s and continue to wield power in Afghanistan.

"The elements that have been dealing with the U.S. government basically want a deal."

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WASHINGTON -- The father of Bowe Bergdahl, a U.S. soldier held prisoner by the Taliban since 2009, is so frustrated that more than a year of covert diplomacy has been unable to free his son that he is learning the Pashto language so he can contact militants directly.

Speaking out about his son's case after a long silence, UPS worker Bob Bergdahl urged President Barack Obama's administration to push harder for his release. 

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The soldier's father added that he intends to take matters into his own hands, studying Pashto -- the language spoken in southern Afghanistan -- reaching out to regional experts and contacting the media-savvy Taliban through its website.

"I feel that I have to do my job as his father," he said. "I'm working toward a diplomatic and humanitarian solution."

Bob Berghdal said he and his wife Jani are disappointed their son, now 26, remains in danger after almost three years of captivity.

"We believe that Bowe's specific situation is not being addressed," Bergdahl told Reuters in an interview.

Peace talks suspended
The missing serviceman's fate is tied up in U.S. efforts to broker a peace deal between the Taliban and the Afghan government, a high-level, high-risk diplomatic initiative which appeared to be on the cusp of a breakthrough before the Taliban suspended preliminary talks in March.

In a separate interview with the Idaho Mountain Express, Bob Bergdahl said there was "a dynamic here that has to change."

"Everybody is frustrated with how slowly the process has evolved," he added. 

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Bob Bergdahl told the newspaper that swapping Taliban prisoners at Guantanamo for his son represents a "win-win" for the United States. He said in addition to his son's safe return, the United States could foster good will with the Afghan people.

Bergdahl, of Hailey, Idaho, was stationed in Paktika province, a hotbed of militant activity, when he disappeared in unclear circumstances on June 30, 2009. He is believed to be held by the Haqqani network, an insurgent group affiliated with the Taliban, probably somewhere in Pakistan.

The family appears even more frustrated that prospects for progress seem to have dimmed in Washington, where the idea of negotiating with the shadowy militant group has exposed the White House to political attack in the run-up to the presidential elections.

For months, U.S. negotiators were seeking to arrange the transfer of five Taliban detainees held at Guantanamo Bay military prison to the Gulf state of Qatar. The transfer was intended as one of a series of confidence-building measures designed to open the door to political talks between the Taliban and Afghan President Hamid Karzai's government.

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That move -- at the center of U.S. strategy for ending the long, costly conflict in Afghanistan -- was also supposed to lead directly to Bowe's release. The Taliban has consistently called for the United States to release those held at Guantanamo Bay in exchange for freeing Western prisoners.

The Guantanamo transfer proposal, which would have required notification to Congress, ground to a halt when the Taliban rejected U.S. conditions designed to ensure transferred Taliban would not slip away and re-emerge as military leaders.

While most American officials do not expect that proposal to be taken up again in earnest in the months leading up to the Nov. 6 presidential election, they are exploring alternative steps they hope might rekindle the process.

The prospect of a quick start to peace talks grows more unlikely just as questions mount about what the West, after over 10 years of war in Afghanistan, will be able to accomplish before NATO withdraws most of its troops at the end of 2014.

From the start, the Guantanamo transfer plan drew fire from politicians on Capitol Hill who, according to U.S. law, would have had to closely examine the proposal. The criticism came not just from leading Republicans, but also from some Democrats.

The Bergdahl family said it believes the opposition may have been too intense at a time when the administration is seeking to burnish Obama's national security credentials. "It doesn't seem like dialogue is even allowed" by Congress, Bergdahl said.

Mitt Romney, the presumptive Republican presidential nominee, also has rejected the proposed transfer. "We do not negotiate with terrorists," he said in December.

'Too much risk'
The imprisonment of suspected militants at Guantanamo is an irritant in U.S. relations with Muslim nations including Afghanistan, which has long demanded the release of its citizens held since shortly after the U.S. invasion that toppled the Taliban government in Kabul in 2001.

Bob Bergdahl said he does not advocate an attempt to rescue his son by force. 

"That's too much risk, for too many people," said Bergdahl, who described Bowe as a "soft-spoken," "compassionate" young man who, as a home-schooled youth, was a skilled outdoorsman drawn to martial arts and biking.

A senior U.S. military official told The Associated Press that the Pentagon believes Bergdahl to be alive and in relatively good health. The official spoke on condition of anonymity because efforts to free Bergdahl remain sensitive.

A senior Obama administration official, also speaking on condition of anonymity because of concerns for Bergdahl's safety, told reporters that the case has been a topic at each of several direct meetings that U.S. officials have held with the Taliban. Direct contact, once taboo for the United States, began in secret last year in hopes that the channel could speed larger peace talks with the Afghan government of President Hamid Karzai and ultimately end the long Taliban insurgency.

The official said the U.S. hopes to revive the Bergdahl deal with the Taliban.

Marine Col. David Lapan, spokesman for Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told reporters that the military has a "collaborative" relationship with Bergdahl's family, which is given quarterly updates from Washington. He said the family is not advised on whether to discuss the case with the news media.

"Our message to them is: We are working hard to obtain Sgt. Bergdahl's release, to bring him back into U.S. hands," Lapan said.

Asked about the family's complaint that the U.S. government has not done enough, Lapan said: "It's perfectly understandable that parents whose son has been kept in captivity for several years now are frustrated. We certainly understand that. That's why we do everything thing we can to try to keep them updated, to the extent we can."

He added: "If they are angry and/or frustrated, that is certainly understandable. I would say that our leaders are frustrated as well."

The last time the Bergdahls saw their son was the Christmas holiday of 2008, when he came home from his military service just months before shipping out to Afghanistan.

To solicit support for further action, Bob Bergdahl plans to speak at an annual demonstration to recognize prisoners of war over Memorial Day weekend in Washington. The event, organized by the nonprofit POW support group Rolling Thunder, typically attracts more than 100,000 motorcyclists to the nation's capital.

Reuters and The Associated Press contributed to this report.

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