Prime Minister David Cameron is expected to address claims that three British men were tortured by police in Dubai when he meets the president of the United Arab Emirates this week.
The state visit by Sheikh Khalifa bin Zayed Al Nahyan comes amid allegations that Grant Cameron and Suneet Jeerh, both 25, and Karl Williams, 26, were tortured by police.
Mr Williams and Mr Cameron, both from Wanstead, north-east London, and Mr Jeerh, from Ilford, east London, have been jailed for four years each for possessing drugs in Dubai.
They were convicted of possessing synthetic cannabis after being arrested in July last year while on holiday. Charges that they had supplied the drug were dropped.
The men claim they signed documents in Arabic - a language none of them understands - following their arrests after they were threatened with guns to their heads. Mr Williams also reported having electric shocks administered to his testicles.
The Foreign Office has called for a full, independent and impartial inquiry into the torture allegations and has raised them with "very senior officials" in the UAE. And Mr Cameron is expected to discuss the allegations with the sheikh on Wednesday.
His spokesman said there were "no no-go areas" for the discussions, adding: "We have asked for a full, impartial and independent investigation into the incidents. We have a state visit, we have an opportunity to build and strengthen relations between our two countries and as part of that we will be talking about a wide range of issues which will include concern about these cases."
The case has been taken up by pressure group Reprieve, which campaigns on behalf of prisoners, and has called for clemency for the men, and that their torture allegations be thoroughly investigated.
Reprieve investigator Kate Higham said: "The central fact of this case remains that these men were tortured by police, but there has been no proper investigation into their abuse. The only reasonable course of action for the UAE authorities now is to grant these men clemency, release them and allow them to return home to their families.
"David Cameron must push for this when UAE President Sheikh Khalifa arrives on a state visit tomorrow. It also remains essential that the UAE conduct an impartial investigation into these men's torture and ensure it is never allowed to happen again."