(CNN) -- The United States has acted to transfer to Afghanistan's custody the prisoners it is holding in that country, but a top commander says those who pose a threat will not be moved.
The issue of custody of prisoners in Afghanistan has long been a sticking point between the two countries ahead of a planned withdrawal of American troops in 2014.
There was White House support to see the transfers through, but unease crept in after Afghan President Hamid Karzai said many of the prisoners are innocent and promised to release them.
The commander of the International Security Assistance Force, Gen. Joseph Dunford, stated unequivocally Saturday that the United States will ensure than anyone deemed a threat remains detained. The ISAF is under the NATO umbrella.
"I think there's probably a difference of opinion," Dunford said, referring to Karzai's assertion that many prisoners are innocent. "We certainly don't have anyone in the detention facility that we think doesn't deserve to be there, in order to protect our forces."
As recently this week, Gen. James Mattis, commander of U.S. Central Command, told Congress that he supports the transfer of prisoners in part because there is a "dual-key" system where both countries have a say in who is released.
Dunford said the United States would do what it takes to keep certain detainees in prison.
"If there's a threat to the force, we will not conduct the transfer," he said. "One thing that we will do is ensure that the young men and women that are over here in harm's way are provided adequate protection. If there are people that need to be detained, we will make sure they are detained."
The ISAF commander also addressed a disparity in numbers being suggested for U.S. troop levels in Afghanistan past 2014. Mattis recently called for 13,600 troops, but the White House has figured on fewer than half that number.
No decision has been made on how many troops will remain and are under review, he said.
"General Mattis and I have never talked specific numbers. I'm in the process now of answering some questions and making some recommendations," Dunford said.
Dunford said he met with Karzai on Saturday to discuss another issue between the two countries, the order by Karzai for U.S. Special Forces withdraw from Wardak Province, which is just west of the capital of Kabul, by this week.
There is still room for compromise, he said.
"His minister of defense was there, and we agreed to continue to work this issue with his minister, to ensure that we have adequate protection for the force, that we were gonna accomplish our security mission in Wardak, and also meet his concerns about moving Afghan forces in the lead," he said.