The assisted suicides of an elderly British couple at a Swiss clinic rekindled the fierce debate Friday over whether Britain should modify its laws to allow terminally ill patients to end their lives with a doctor's help.

A neighbor in the city of Bath, where Peter and Penelope Duff lived, said they were suffering from advanced stages of cancer.

"They were so close and they both had this dread disease and they would not have wanted to live on without the other," said David Keeling, who saw the couple over the Christmas holidays.

"They were not looking well," he said. "Peter was an extremely organized man and I believe he had this all organized at that time."

Ludwig Minelli, director of the Dignitas clinic in Switzerland, said Friday that Peter Duff, 80, and his 70-year-old wife died on Feb. 27, becoming the second British couple to have ended their lives at the clinic.

He said the clinic was operating within Swiss federal law that gives people "the right to decide for themselves where and when they want to die."

The legal criteria, he said, was that the patient be able to make their own decision and be capable of carrying out the "final act" that leads to death.

British law is quite different. Doctors, friends and family members who help someone end their lives can face up to 14 years in prison.

Right-to-die campaigners say terminally ill Britons seeking to commit suicide have to travel abroad to do so and sometimes end their lives earlier than is necessary because they fear growing too weak to travel, and then being kept alive against their will.

"We want the laws to be changed so that mentally competent adults who are suffering unbearably have the option of assisted deaths," said Sarah Wootton, the chief executive of Dignity in Dying. "They might well have been eligible under that legislation, so traveling wouldn't have been a factor, and they might still be alive."

The group is lobbying for a liberalization of Britain's suicide laws, taking into account medical advances that can keep people alive despite a severe decline in their quality of life.

Parliament has been reluctant to make changes, although public prosecutions have become rare. Officials took a lenient view in December, for example, after the parents of a paralyzed 23-year-old man helped him end his life at Dignitas.

The Duffs' daughter, Helena Conibear, released a statement praising her parents' bravery but declining to elaborate on the circumstances for legal reasons.

Peter Duff was a successful wine merchant and consultant who had helped found the Wine Guild of the United Kingdom and was also played a leadership role with the Alcohol in Moderation group.

He and his wife were art collectors with an expansive Georgian house in the Roman spa town of Bath, 115 miles (185 kilometers) west of London, and a second home in Dorset.

Keeling said he is sympathetic with his neighbors' heart-rending decision to end their lives.

"As a Catholic, my church says no," he said. "But my heart is elsewhere."