The Netherlands, where so-called mercy killings have been tolerated for decades, yesterday became the first state to vote to legalise euthanasia.
The lower chamber of parliament voted by 104 to 40 to approve a Bill allowing doctors to help patients die under a strict set of rules. Upper chamber approval is seen as a formality.
The Bill's supporters say it champions patients' rights and brings a long-standing practice into the open. But many religious and medical groups were swift to condemn the law, claiming killing would replace caring.
"Again we are faced with a law of the state which opposes the natural law of human conscience," the Vatican spokesman, Dr Joaquin Navarro-Valls, told Reuters.
Dutch Calvinist opposition parties fear the proposed law will be abused. Some drew parallels with Nazi Germany.
"The same line of reasoning is being used as in Germany in 1935 . . . In the Netherlands, your life is no longer safe," said Mr Bert Dorenbos of the Scream for Life group.
"If doctors are not hesitating to kill people, then they will not hesitate to withdraw medical treatment from people they do not like," he added.
The Dutch Bill moves the legal goalposts on a controversial and emotional issue which ranks alongside abortion.
Australia's Northern Territory legalised medically assisted suicide for terminally-ill patients in 1996, but this was later overturned.
Other countries, such as Colombia and Switzerland, have ruled that it is not a crime to help a terminally-ill person to die as long as they have given clear and precise consent.
But the Dutch Roman Catholic Church said it would now be too easy for people to give up. About 34 per cent of the Dutch are Catholics, 25 per cent Protestant and 36 per cent not affiliated to any church.
"People who are ill but consider themselves a burden to their family, that's the problem," said Mr Peter van Zoest, spokesman for the Bishops' Conference.
"The Netherlands is the first country to legalise euthanasia since the Nazis," Dr Monika Schweihoff of the German hospital foundation said in a statement. "Euthanasia is not the only option - qualified hospice staff can also help terminally-ill patients slip away painlessly."
Recent figures show that Dutch doctors helped 2,216 patients, mostly cancer victims, to die in 1999. But it is estimated that some 60 per cent of cases are not reported.