The Nato-led mission in Afghanistan has suspended the transfer of detainees to several Afghan jails, following torture allegations, the BBC has learned.
The accusations come in an as-yet unpublished UN report, which describes how prisoners were beaten and in some cases given electric shocks.
The jails are run by the Afghan police and intelligence service.
A Nato official said it was a "prudent" measure until the allegations could be investigated.
"With appropriate caution, Isaf [International Security and Assistance Force] has taken the prudent measure to suspend detainee transfer to certain facilities until we can verify the observations of a pending Unama [UN Mission in Afghanistan] report," a Nato official told the BBC.
The facilities that are involved are prisons run by the Afghan National Department of Security (NDS) in Herat, Khost, Lagman, Kapisa and Takhar as well as the NDS' Counter-Terrorism prison, known as Department 124.
Isaf has also suspended the transfer of detainees to two prisons run by the Afghan Police in Kunduz and Tarin Kowt.
The transfer of prisoners in restive Kandahar province has already ended.
The BBC has learned the report describes the torture as commonplace and systematic.
Prisoners, some of whom had been handed over by Nato troops, were beaten with rubber hoses and threatened with sexual assault.
Most of those held were suspected of being insurgents and some were held without charge.
The UN mission in the country said it had already shared the report's findings with the government of Afghanistan.
"We understand they are taking the findings very seriously and are proposing a series of remedial actions," the mission's spokesperson Dan McNorton said.
"Our findings indicate that the mistreatment of detainees is not an institutional or government policy of the government of Afghanistan."
One official from Isaf described the report as a major setback.
The Nato-led mission plans to bring foreign troops home, by handing more responsibility to Afghans but there are concerns that in some areas, Afghan security forces cannot be trusted.
Last year, Britain's Ministry of Defence (MoD) agreed to halt the transfer of prisoners to NDS jails in Kabul, after a court ruled that they faced the risk of torture or serious mistreatment.
Prisoners are still transferred in the southern province of Helmand, but under strict supervision, according to the MoD.