The Government is abdicating its responsibilities towards vulnerable members of society by failing to implement laws on assisted suicide, it was claimed yesterday.

The Voluntary Euthanasia Society said that by not introducing legislation, it was "inevitable" that more people, including those who were not terminally ill, could become so-called "suicide tourists".

Fresh concerns have been raised about assisted suicide following the deaths of British couple Robert and Jennifer Stokes, who died in Switzerland on April 1. They had not been terminally ill.

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

The couple, who were 59 and 53, had travelled to Swiss city of Zurich from their home in Leighton Buzzard, Bedfordshire, after contacting the charity Dignitas. The organisation helps the terminally ill to end their lives thanks to loopholes in Swiss law.

Deborah Annetts, chief executive, of the Voluntary Euthanasia Society, described the couple's case and others like them as "horrifying".

She said: "It's very important that people think about the implications. Doctors also have an obligation to outline options such as palliative care.

"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."

Asked if publicity surrounding Dignitas and people like the Stokes could lead to an increase in people travelling abroad to end their lives, she said: "It's inevitable. Unless the Government acts and puts in place laws on assisted suicide, more and more people will die this way. That's an abdication of responsibility."

Dr Anthony Cole, chairman of the Medical Ethics Alliance, said that he and his colleagues were "saddened and dismayed" that people with treatable diseases were being helped to die by overdosing.

Last week, inquests into the deaths of Mr and Mrs Stokes were opened and adjourned to a date to be fixed pending the outcome of toxicology tests.