(CNN) -- The United States appeared Monday to raise the possibility there may be no long-term strategic agreement with Afghanistan after American troops withdraw in 2014, a move that comes amid heightened tensions over the burning of Qurans by U.S. soldiers.
The sticking point in negotiations over a Strategic Partnership Agreement, which would provide support and aid to Afghanistan, appears to be an end to night raids and speed up a timeline to hand over U.S.-run detention facilities.
No one in Washington or Kabul has publicly said the two countries are at an impasse, though the negotiations have dragged on for nearly a year.
Over the weekend, the United States released a brief statement that for the first time appeared to question whether an agreement could be reached.
"We have always said it was more important to get the right agreement than to get an agreement," Gavin Sundwall, a spokesman for the U.S. Embassy in Kabul, said in a written statement.
Without a strategic partnership, it is unlikely there would be any agreement to extend U.S. troops beyond a 2014 deadline to withdraw from Afghanistan.
Afghan President Hamid Karzai was scheduled to meet Monday with U.S. Ambassador Ryan Crocker to discuss the agreement, said Karzai spokesman Aimal Faizi.
Faizi would not comment on speculation of a possible breakdown in talks, saying the Afghan government had received no such formal notification.
Karzai has repeatedly said he wants all prisoners handed over to Afghan control and an end to night raids, requests the U.S. military has previously resisted.
"The United States has repeatedly made clear that it is committed to working with the Afghan government to complete a transition of detention operations in Afghanistan in a manner that is safe and orderly, and in accordance with our international legal obligations," Sundwall said.
"We will continue to work with the Afghan government to meet this objective, as part of our broader transition efforts."
The possibility that the United States may not be able to come to an agreement with Afghanistan raises questions about the stability of the country once the U.S. military and other members of the NATO-led International Security Assistance Force withdraw.
A break down in talks between the U.S. and Iraq over the extension of American troops led President Barack Obama to announce he would pull virtually all troops ahead of a December 31, 2011, withdrawal deadline.
Talks broke down after Iraq's top political leaders refused to grant U.S. troops legal immunity, opening up the prospect of soldiers being tried in Iraqi courts and being subject to Iraqi punishment.
There is concern that the United States could face a similar issue in Afghanistan over demands by senior Afghan clerics that American soldiers involved in the burning of Qurans be put on public trial, perhaps even in an Afghan court, something that most military observers agree will never happen.
Five American soldiers and an Afghan translator were involved in the burning of the Qurans, which were among religious materials seized from a detainee facility at Bagram Airfield in February, a NATO official speaking on condition of anonymity told CNN earlier.
Obama apologized to Karzai, calling the burning inadvertent.
Furor over the burnings fueled a string of violent protests and attacks that have left dozens dead, including four American soldiers. Hundreds more have been wounded in the attacks.
There are Afghan and NATO investigations underway into the destruction of the Muslim holy book, which has raised fears that conflicting findings in the different investigations could reignite the violence.
CNN's Chelsea J. Carter contributed to this report