Efforts to start peace talks with the Taliban appear to be gaining traction, with the head of the Afghan peace council saying Saturday that it has been in contact with three factions of the insurgent movement and the U.S. defense secretary predicting negotiations by the end of the year.

Other signs also suggest that discussions with insurgents are moving forward.

Marc Grossman, the U.S. special envoy to Afghanistan and Pakistan, has reached out directly or indirectly to three insurgent groups, although it's unclear how the efforts by the peace council and the U.S. dovetail, Western officials say.

The United Nations will give a thumb's up or thumb's down later this month on whether to take Taliban figures off a U.N. sanctions blacklist list -- a move that could enable prospective intermediaries to travel abroad to hold talks.

One Western official has told The Associated Press that the fate of the only U.S. soldier being held by insurgents has been mentioned in recent preliminary discussions between the Americans and Tayyab Aga, the former personal secretary to the Taliban's one-eyed leader Mullah Mohammed Omar. The U.S. is asking what it will take to win the release of Spc. Bowe Bergdahl of Hailey, Idaho, who will mark two years in captivity on June 30.

It's not clear whether Aga still has links to Omar or whether Omar supports contacts with U.S. officials. The Taliban have flatly denied that anyone is talking to the U.S. or to the Afghan government, and senior Pakistani security officials say Omar is rigid in his refusal to negotiate.

At a news conference Saturday in the Afghan capital with President Hamid Karzai, U.S. Secretary of Defense Robert Gates said if the U.S.-led coalition and Afghan forces can hold territory captured from the Taliban, and even expand that security "we will be in a position towards the end of this year to perhaps have a successful opening to reconciliation."

But Gates, who's retiring June 30, said much depends on whether the May 2 death of al-Qaida leader Osama bin Laden creates a new opening.

A day earlier in Singapore, Gates said it was important to maintain military pressure on the Taliban to reach a peace deal.

The Taliban publicly insist they have no interest in negotiating peace so long as foreign troops occupy Afghanistan. President Barack Obama is due to make a decision on U.S. troop reductions in the next couple of weeks.

More than 200 NATO troops have been killed in Afghanistan this year, including four who died Saturday in an explosion in the east of the country.

Richard Barrett, coordinator for the U.N.'s al-Qaida and Taliban monitoring team, said he didn't think the Taliban were feeling "so weak that they have to negotiate or else be eradicated. Nor do I think they rule out the possibility of talks."

"The Taliban are feeling the ground just like the Americans and everybody else is. Talks are in the early stages," he said.

He said Karzai has requested that just under 50 Taliban figures be taken off the U.N. sanctions list, which keeps them subject to an asset freeze and travel ban. More than 100 Taliban members are on the list.

The U.N Security Council committee monitoring the sanctions will make a decision on June 16 on the latest tranche of roughly 30 individuals, Barrett said. The Afghan government has provided the committee with extensive dossiers on about 20 of them with information about why it believes these individuals should no longer be sanctioned, he said.

Those with the extensive documentation include Sayed Rahman Haqani, a former deputy minister of mines and public works in the Taliban regime, as well as four members of the peace council. The council members are: Arsala Rahmani, the Taliban's former deputy minister of higher education; Habibullah Fawzi, who once served as the Taliban's ambassador to Saudi Arabia; Faqir Mohammad Khan, a former Taliban deputy minister; and Sar Andaz Qalamuddin, a former top official in the Taliban's hardline religious police -- known as the vice and virtue unit.

Russia, a permanent member of the U.N. Security Council that holds veto power, has been reluctant to approve requests to delist members of the Taliban. Barrett, however, said the Russians could be amenable in some cases.

"Russia will want to look at the cases very thoroughly, but by no means will they refuse to delist anybody and everybody just because they're Taliban," he said.

Former Afghan President Burhanuddin Rabbani, who is head of the peace council that Karzai set up to facilitate contacts with insurgents, told members of parliament Saturday that in the past five months the council has made contacts with: the Taliban governed by the Quetta shura, named for Pakistan's southeastern city where many of the Taliban are said to live or transit with relative ease; the al-Qaida affiliated Haqqani network; and the insurgent group run by Gulbuddin Hekmatyar, who is on a U.S. designated terrorist list.

Even talks about talks with the Taliban have prompted rising concern from ethnic minorities and women's groups in Afghanistan. They worry that negotiations with the Taliban, comprised mostly of majority Pashtuns, will open a path for the hard-line fundamentalist group to regain power -- or exact painful concessions.

The Taliban, who were ousted by the 2001 U.S. invasion for harboring al-Qaida, banned women from most jobs and education during their years in power.

Discussions the U.S. is having with Tayyab Aga are still in the exploratory stage, according to the Western official. It wasn't clear whether Aga made the first overture to the U.S. or whether it was the U.S. who contacted him.

Aga has made no commitments, but comments like "Would this help Bergdahl?" have been raised in the meetings, according to the official, who declined to give more specifics.

Aga is just one of several insurgents the U.S. reportedly has approached either directly or indirectly to test their willingness to talk peace, according to Western diplomats. Others include former Taliban information minister Qatradullah Jamal. Lines also are out to representatives of the network run by Hekmatyar and Ibrahim Haqqani, a brother of group leader Jalaluddin Haqqani.

All the Western diplomats spoke on condition of anonymity in exchange for disclosing details about confidential talks.

A senior Pakistani intelligence official told the AP that so far, the nation's intelligence service has not been asked to approach any of the insurgent groups about peace talks. The official, who also asked not to be named because he wasn't authorized to release the information, said that the United States has had full access to members of the Afghan Taliban in Pakistani custody, including Mullah Abdul Ghani Baradar, the former Taliban No. 2.