The High Court has made an order preventing the Government from resuming the transfer of detainees captured by British forces in Afghanistan to the Afghan authorities until a legal challenge has been heard.
The injunction will remain in place until judges have had a chance to rule in a hearing later this month on whether there is currently "a real risk" that detainees may face torture.
Transfers had been suspended in a moratorium ordered by Defence Secretary Philip Hammond in April following concerns that detainees had suffered abuse. Mr Hammond decided in October that transfers could safely start again.
But lawyers for one detainee, Serdar Mohammed, argued at London's High Court that there was a real risk of torture if detainees were handed over to the Afghan National Directorate of Security (NDS) - the Afghan intelligence service.
Dinah Rose QC, representing Mr Mohammed, said he had been tortured and the Defence Secretary's evidence that transfers may now safely take place was "highly contentious".
She argued no transfers should be resumed before the minister's decision could be challenged at a judicial review application due to start on November 27. Lord Justice Moses and Mr Justice Simon agreed.
Lord Justice Moses said: "It seems to me that that which caused the Ministry of Defence to impose a moratorium raises the very question that justifies imposition of interim relief."
Mr Justice Simon agreed but stressed the court had not reached a conclusion on the ultimate merits of Mr Mohammed's case.
Solicitor Richard Stein, who represented Mr Mohammed, said afterwards: "We are relieved the ring has been held until trial and the serious breaches of justice and risk to those being held by British forces in Afghanistan will be held until after the trial of this case."
Reprieve's legal director Kat Craig said: "It is shocking that the Government is trying to lift a ban on transfers to the Afghan security services with one hand, while covering up evidence of torture with the other. For now, they have not succeeded, but should plans for secret courts pass Parliament this will become child's play."