Campaigners for euthanasia claimed yesterday that a failure to make assisted suicide legal in Britain was driving people abroad to end their lives.

The case of Robert and Jennifer Stokes, a couple from Bedfordshire who were helped to die by a Swiss euthanasia group, has renewed concern about "suicide tourism". Mrs Stokes is believed to have attempted suicide before. The couple both suffered chronic, but not terminal, illnesses.

Deborah Annetts, chief executive of the Voluntary Euthanasia Society, described the Swiss system as "death on demand" and warned that publicity surrounding the deaths in Zurich was encouraging other Britons to follow suit. She urged the government to adopt a bill sponsored by Lord Joffe, a retired human rights lawyer, which would allow a terminally ill adult in unbearable pain to receive medical help to die.

The patient (assisted dying) bill requires the patient to consider alternatives and have their diagnosis confirmed by two doctors. But it has no government backing and is unlikely to become law.

Although the proposed law would not have enabled the Bedfordshire couple to commit suicide legally, another of the bill's aims is to promote communication between the doctor and the patient.

Ms Annetts said: "If the patient said to the doctor, my life is awful and I want help to die, and they are not suffering terminal illness, the doctor should become aware that there is a serious problem here that needs to be addressed. Nobody sat down with them and said you could have this, that and the other. That's the direct result of having no legislation in place.

"What is coming out of the Netherlands is that, if you put in place tightly defined legislation, because there is the option of assisted death, very often people go on to live."

Following the couple's deaths, it emerged that Mrs Stokes had a history of suicide attempts. According to her ex-husband, Peter Underwood, she was unstable and frequently took overdoses of tablets during their 11-year marriage.

She and Mr Stokes were Jehovah's Witnesses, whose beliefs prohibit suicide.

Mr Stokes had epilepsy and is believed to have undergone brain surgery to cure chronic depression while his wife was diabetic and had arthritis that affected her spine.

Vivienne Nathanson, head of science and ethics at the British Medical Association, which opposes euthanasia, said a doctor's priority should be to enhance a patient's quality of life. "Very often when people seek euthanasia, or raise the issue, what they are saying is, 'do you still value me?' The job of the doctor is to relieve suffering, but it is also to help people get the most out of whatever life they have left."

A Department of Health spokeswoman said the government had no plans to change the law.

Last year 55 people who wanted to die travelled to Switzerland, most of them dying in a Zurich apartment rented by the euthanasia group Dignitas.

The following correction was printed in the Guardian's Correction and Clarifications column, Thursday April 17 2003

The above report states that "Last year 55 people who wanted to die travelled to Switzerland" and in the context of the article the impression could have been given that they came from this country. The statistics do not specify nationality.