KABUL, Afghanistan -- Afghanistan's government reaffirmed support Sunday for possible talks with its Taliban foes, but demanded full explanations on how the group was allowed to raise its flag in Qatar and display other symbols that have stalled the U.S.-led effort.

The ongoing dispute over the Taliban compound in Doha -- which the Afghan government said appeared as something akin to an embassy in exile instead of just a political outpost when it opened -- underscore the extreme difficulties in just trying to launch dialogue after nearly 12 years of war in Afghanistan.

The Afghan peace process, which has made little headway since it began several years ago, is hobbled by distrust among the major players, with the Taliban steadfastly refusing to talk to the Afghan government. While talks with the Taliban remained stalled, there are signs of increasing efforts to get them back on track. U.S.-backed talks broke down nearly two years ago in a dispute over the release of five Taliban detainees held in U.S. custody at a military prison in Guantanamo Bay, Cuba.

With Afghan presidential elections and the withdrawal of most foreign combat troops looming in 2014, the long-stalled Afghan peace process has taken on added urgency. The Taliban have refused to negotiate with Afghan President Hamid Karzai's government, saying the U.S. holds effective control in Afghanistan, but the Americans are hoping to pave the way for talks between the two sides to begin before pulling out most of its forces.

The Obama administration said last week that the talks would begin with bilateral meetings between the Americans and Taliban representatives 'in a few days,' then eventually extend to include the Afghan government.

However, the Taliban's use of its old flag and a sign bearing the name of the Islamic Emirate of Afghanistan, which the movement used during its five-year rule that ended in 2001 with the U.S.-led invasion, at Tuesday's office opening in the Qatari capital brought sharp complaints across all party lines in Afghanistan.

Kerry used a stop in Qatar on Saturday to urge the Taliban to make good faith efforts to open talks and begin what he called the "difficult" road ahead. He also warned the Taliban may have to close their office if they don't negotiate in good faith.

Under pressure from Qatar, the Taliban lowered the flag and removed the sign.

The Taliban say they have made no concessions after Kerry's warnings. A spokesman in Doha, Shaheen Suhail, has urged all sides to press forward with the process in comments made hours before Kerry arrived in Doha. He said members of the Islamic movement are still having an internal discussion over whether to comply.

Security was boosted at the office on Sunday, but there were no apparent signs of meetings or other diplomatic activity, and no flag was visible from the street.

The main U.S. envoy trying to spearhead the talks, James Dobbins, met with Qatari officials in Doha and planned to travel to Kabul on Monday in apparent bids at shuttle diplomacy.

Suhail said in a telephone call on Sunday that the Taliban had been ready for talks with the United States followed by a dialogue involving all Afghan groups. He did not say what the Taliban thinking was as a result of the latest flap. However he made it clear that the Taliban have not changed their position on the presence of foreign troops in Afghanistan nor have they offered to allow foreign troops after 2014.

"Any side in the negotiations can bring their items to the table. Once talks start the Americans are free to bring their items to be discussed and we are free to bring our items to be discussed," said Suhail. "We have not said anything about foreign troops. Everyone, the American and Taliban side, are free to bring to the table whatever negotiation points they want."

Afghan Foreign Ministry spokesman Janan Mosazai said Sunday that Karzai's government remains willing to send a peace delegation to Doha to negotiate with the Taliban -- but only after it receives explanations over the office opening and assurances that the site does not suggest a diplomatic revival by the Taliban.

"The Afghan government remains fully committed to pursuing a process of peace negotiations with the armed opposition, including the Taliban, but within the confines of the conditions and the principles and the assurances that we have established," Mosazai told reporters in Kabul.

Karzai also suspended negotiations with the U.S. over a security agreement that would allow U.S. forces to stay in Afghanistan after 2014 as he demanded that the offending sign and flag be removed.

Both the U.S. and the Qataris said the Taliban had agreed on the pre-approved name but violated the pact at the ribbon cutting ceremony.

In an emailed statement Sunday, however, Taliban spokesman Muhammad Naeem said the use of the flag and name was "done with the agreement of the Qatari government."

"The statement which states that by using the name and raising the flag, the Islamic Emirate somehow violated an agreement... is completely false," Naeem said in an English-language statement.

The Qatari government had no immediate response.

The Afghan spokesman Mosazai said, however, that Afghanistan is still waiting for a full explanation from Washington and guarantees the Taliban will not attempt to revert to its formal name again.

He also suggested that after "initial contacts" between the Taliban and the United States, the Afghan government expects to lead official peace talks and would push to move them to Afghanistan.

In Tehran, Foreign Ministry spokesman Abbas Araghchi dismissed the U.S. role in peace talks, saying only negotiations among Afghan factions can help stabilize the country.

"Talks with a role by foreigners will not bear any fruit," he said.

Iran once considered the Taliban an enemy, but relations have improved as Tehran expanded its influence in Afghanistan over the past decade.