Vehicles and aircraft are seen parked at the Bagram Air Base, 50 kilometers (31 miles) north of Kabul, on September 11, 2011.

Story highlights

The United States transfers control of Parwan detainees

The handover of the facility has been a sticking point between U.S. and Afghan authorities

The handover took place a year after the initial plan was announced

Originally, the transfer was to have taken place within six months

CNN  — 

The United States on Monday handed over control of a U.S.-run prison near Bagram Air Base to Afghan authorities.

The handover of control of the detention center in Parwan fulfills an agreement between Defense Secretary Chuck Hagel and Afghan President Hamid Karzai.

The detention facility has been a sticking point between U.S. and Afghan authorities, and tensions over the facility re-emerged this month with sharp words from Karzai that the commander of NATO’s International Security Assistance Force called “inflammatory.”

The handover deal was reached Saturday, but came a full year after the initial plan was announced by U.S and Afghan authorities.

The original plan called for the prison and detainees to be handed over with six months, but in September, the United States “paused” the transfer of detainees, which include suspected Taliban militants and insurgents.

The U.S. military has not publicly discussed the specifics of the dispute. But a military official, speaking on the condition of anonymity, told CNN last year that the United States was holding on to several detainees over concerns about whether Afghan authorities will properly handle their cases and under what circumstances they might be released.

Karzai has been adamant that all prisoners be under Afghan control. Last year, he called the U.S. failure to hand over all detainees at the facility a “serious breach” in the deal outlining the transfer of power from U.S. forces to Afghanistan.

Tensions between the NATO-led coalition forces – especially those from the United States – and Karzai have escalated since a bomb blast in Kabul earlier this month that killed nine people.

Karzai said afterward that there are “ongoing daily talks between Taliban, American and foreigners in Europe and in the Gulf states.”

The comment effectively claimed the United States was trying to foment continued violence inside Afghanistan, and it was quickly denounced by NATO and U.S. officials.

Some experts say Karzai’s comments have been fueled by frustration over the detention facility not being handed over, which he views as an attack on his country’s sovereignty.

In an e-mail this month to top commanders, U.S. Marine Gen. Joseph Dunford, commander of ISAF, warned of new risks of attacks due to rising tensions between NATO forces and the Afghan president, an ISAF official told CNN.

Karzai’s recent statements “could be a catalyst for some to lash out against our forces – he may also issue orders that put our forces at risk,” Dunford said.

Barbara Starr reported from Washington and Chelsea J. Carter reported from Atlanta. CNN’s Jennifer Z. Deaton and Jake Tapper contributed to this report.