A pregnant Briton who could face a firing squad for allegedly trying to smuggle heroin out of Laos will receive a fair trial, the country's Government said — even though she has yet to be assigned a lawyer.

Human rights groups fear that Samantha Orobator, 20, from South London, will not be able to defend herself properly when her trial — which was due to start today, but has been delayed — begins.

Ms Orobator has been in jail in the Communist country since August, when she was accused of trying to smuggle 1.5lb (0.68kg) of heroin in her luggage. Laos has a mandatory death penalty for those convicted of smuggling more than 1.1lb (0.5kg).

Anna Morris, a lawyer with the British-based human rights group Reprieve, said she was concerned that trial would not meet the judicial standards of most countries.

"She hasn’t been appointed a lawyer yet and that has been our concern," Ms Morris said. "We are concerned that any hearing may be quite quick in comparison to what will happen in other countries."

Ms Morris, who has travelled to Vientiane, the country’s capital, has been granted permission to meet Ms Orobator. She said that the group was worried about Ms Orobator's health.

Reprieve says that she is five months pregnant, having been in custody for more than eight months. It could not confirm whether she was raped in prison, and the circumstances of her pregnancy remain unclear.

"We are concerned about the effect of the uncertainty on Sam’s wellbeing ... given her age, her vulnerability, her pregnancy," Ms Morris said. "We just seek clarity from the Laos Government as soon as possible as to what exactly is going to happen so that we can advise her properly."

Ms Orobator had been in jail for months before the British Government learnt of her detention. British authorities have been able to visit her only for 20 minutes, once a month.

The British vice-consul from Bangkok in neighbouring Thailand flew to Laos yesterday to try to see Ms Orobator. Bill Rammell, the Foreign Office Minister, said that he would raise the case with the Laotian Deputy Prime Minister when they meet in Britain on Thursday.

Ms Morris said: "There has been a significant shift in this trial date. We are still unclear as to the reason for that.

"We are working closely with the British Embassy in Thailand and are encouraging them to do whatever is necessary to put pressure on the authorities to ensure her welfare."

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