Doctors' leaders want a change in the law to make every citizen a potential organ donor. They want to copy Belgium, France and Spain where everyone is deemed a willing donor unless they carry a card saying they do not want organs removed for transplants.

The British Medical Association says "presumed consent" would save thousands of lives a year. Organ donation in the UK is at a 12-year low, with nearly 6,500 people waiting for transplants and just 2,250 transplant operations last year. Despite a series of high-profile publicity campaigns, including an appeal by Tony and Cherie Blair, less than one in five people carries a red, white and blue organ donor card.

Next month the BMA will publish a policy document calling for the law change. The Association admits it faces a delicate task because "presumed consent" can work only with the support of the public. That is difficult, particularly after last week's revelation that Alder Hey Hospital, Liverpool, where organs from 800 children were held without parental consent, had lost one child's brain, heart and lungs.

Dr Michael Wilkes, chairman of the BMA's ethics committee, says the change is the only way to stop thousands of people dying needlessly while they wait for organs.

The birth of five cloned piglets last week was hailed as a major step towards an unlimited supply of pig organs customised with human genes to make them suitable for transplant patients. But Andrew Bradley, professor of surgery at Addenbrookes Hospital in Cambridge, said resolving the ethical, technical and health concerns about xenotransplantation (transplants from animals) will take 10 years. "We need a medium-term solution," he said.

The BMA initiative was welcomed by the British Organ Donors Society. The chairman, John Evans, said: "I would support presumed consent with the backup of family agreement, but we must also improve the NHS transplant co-ordination service which is so much better in some European countries."

The National Kidney Research Foundation say public debate about organ donation must be opened up. Paul Caine, of Workington in Cumbria, who had a kidney from his brother in 1998 after a transplant from 1990 failed, plans to stand as a parliamentary candidate on "a presumed consent ticket". He said: "A kidney transplant saved my life. If you saw someone drowning you would rush to help without a second thought, and presumed consent would mean you could do the same thing when you died."

The presumed consent system has been successful in Belgium, France and Spain, where the health services are closing the gap between organ supply and demand. Professor Bradley said most transplant patients are waiting for kidneys. "Spain has vastly increased its organ donor rate and is beginning to turn around the transplant waiting-list. They also have an excellent system of transplant co-ordination, and public opinion is firmly with presumed consent."

* A hospital has suspended kidney transplants because of pressure on the two surgeons in its understaffed renal unit.

One doctor at the University Hospital of Wales, in Cardiff, has been given leave and the other has stopped operating after 15 days on call. A spokesman, Bob Burrows, said: "The situation is regretted, but the decision is in the best interests of patient care and safety. [The doctors] needed some respite from the pressure". Transplants restart tomorrow.

Earlier this month, a Korean war veteran, Graham Reeves, 70, of Burry Port, west Wales, died after surgeons removed his one healthy kidney by mistake at the Prince Philip Hospital, in Llanelli.