Hundreds of Britons are locked up in squalid conditions overseas, without trial, for drug related offences that could carry a possible death penalty, the Foreign Office has warned.
More than 850 Britons are currently locked up in overseas prisons for drug-related offences, some serving sentences of up to 39 years, while many still wait for their cases to come to court.
This year, British grandmother Lindsay Sandiford was sentenced to death in Bali, Indonesia, for drug-trafficking, and is still fighting her sentence of death by firing squad, having lost her final appeal. In Indonesia, those caught with drugs face lengthy prison sentences or the death penalty, usually after a protracted and expensive legal process.
Police escort Melissa Reid, of Britain, front, and Michaella McCollum Connolly, of Ireland, behind right, from the National Police anti-drug headquarters to a court to be formally charged for drug trafficking in Lima, Peru
In Peru more than 30 Britons are currently in prison for drugs offences. Drug smugglers in the country face long terms of imprisonment. Two of them are two British students, Melissa Reid and Michaella McCollum Connolly, Ibiza nightclub hostess caught with £1.5 million worth of cocaine.
The FCO highlighted the fact that in Thailand being in possession of in excess of 20 grams of a Class A drug could mean your being deemed as a trafficker and could potentially be sentenced to death.
United Arab Emirates' sentences for drug trafficking for possession of even the smallest amount of illegal drugs can lead to a minimum four-year jail sentence.
The FCO said the zero-tolerance approach of some countries often results in strict penalties which can come as a shock to British travellers.
Offences that may carry cautions in the UK are often penalised with long prison sentences when overseas, and in 33 countries or territories some drug offences carry the death sentence.
Prisoners Abroad, a charity which supports Britons stranded in foreign jails, is currently supporting 80 Britons between the ages of 18 and 30 held in foreign countries for drugs offences. Two thirds of these are still awaiting trial while others are serving sentences from a year to nearly 39 years.
Consular affairs minister Mark Simmonds said: "People continue to be astonished at some of the penalties handed down for certain crimes overseas. In some countries possessing small amounts of marijuana can lead to decades in prison.
"In the last year alone consular staff handled over 650 drug-related cases. We want to reduce this number significantly."
He went on: "Laws, penalties and sentences vary considerably around the world for the use, possession and trafficking of all types of drugs. When it comes to drugs our message is clear - don't take risks, the consequences are simply not worth it."
Prisoners Abroad chief executive Pauline Crowe said: "In many countries, men and women find themselves without access to food, clean water and the most basic of medical care.
"We urge people to consider the unsanitary conditions, overcrowded cells and the constant threat of disease before they get involved in drugs. They may have to live through these conditions for many, many years."