The British High Commissioner in Bangladesh has strenuously denied allegations in a British newspaper that it condoned the likely use of torture.
The Guardian newspaper said that British authorities passed information on terror suspects to "notorious" agencies in Dhaka.
It said that ministers did so despite the risk suspects could be tortured.
High Commissioner Stephen Evans told the BBC that the report was inaccurate and that the UK never condoned torture.
"We take all allegations of torture and mistreatment very seriously," Mr Evans said.
"Our security co-operation with other countries is consistent with our laws and with our values."
Mr Evans said that Britain and Bangladesh did however co-operate in the area of law enforcement, "which includes the sharing of information which may be relevant to the security of either country".
The Guardian report on Tuesday said that "a number of British citizens" were held and mistreated at the Taskforce for Interrogation (TFI) cell run by the authorities in Dhaka.
The paper said the cell was where a number of the country's intelligence agencies and police units worked together, extracting information and confessions from enemies of the state.
It said that the methods used involved human suffering and that suspects were reported to have been beaten and subjected to electric shocks - in one room "fingernails were said to have littered the floor".
Bangladeshi authorities have also dismissed the report as "totally a fake and baseless".
"It's unfortunate that a paper like the Guardian can publish such fake and baseless reports particularly with regard to the torture that has been mentioned and also in regard to the TFI centre," Commander M Sohael of the Rapid Action Battalion (RAB) told the BBC.
The Guardian report said the RAB has admitted the extrajudicial killings of hundreds of terror suspects.
The newspaper's story follows similar allegations leaked last month that the UK was training RAB members - accusing the force of being a "death squad".
RAB members were taught "interviewing techniques" and "rules of engagement" by the UK authorities, leaked cables published by the Wikileaks website said.
Mr Evans said that far from being complicit in torture, the UK High Commission in Bangladesh was involved in at least two cases where consular assistance was provided to British nationals arrested in the country.
"We take very seriously all issues relating to the health and welfare of detained British nationals," he said.
The Guardian quoted one British-Bangladeshi suspect as saying that two British security service officers were even present as he was being questioned and beaten by Bangladeshi intelligence officers.
BBC News - UK denies Bangladesh torture allegations