All Britons should be considered organ donors unless they state otherwise, Britain's Chief Medical Officer proposed Tuesday, saying the country faced a severe shortage of organs.
Sir Liam Donaldson, the government's top medical adviser, said in his annual report that an average of one patient died every day waiting for a transplant.
Under current law, organs may be removed from a body only if the person has made his consent known or, if he has not specified his wishes, with the consent of a family member or representative.
Donaldson argued the law tends to discourage organ donation.
The British Medical Association backed the proposal, although it warned that the public would need to be made "completely aware" of the change.
"An opt-out system may be one way to help meet the demand, but if introduced must ensure that those opting in or out did so with informed consent," said Dr. Keith Rigg, the vice president of the British Transplantation Society.
Donaldson said opting out of the system would be clear and easy, and that safeguards would protect vulnerable individuals such as children and the disabled from exploitation.
"The experience of other countries shows that such a system can command public confidence," he said.
Spain, Belgium, the Czech Republic and Austria already have similar arrangements. In some of those countries the rate of donation is nearly double Britain's.
Any changes to the system would have to be made by lawmakers.