The Bishop of Birmingham has criticised proposals to allow the transplant of organs from people who have never signed a donor card.
Under existing rules, the medical profession can only use organs from people who have agreed to become donors. But Health Secretary Alan Johnson yesterday launched an inquiry into creating a system of "presumed consent".
This would give the medical profession the right to use anyone's organs after their death, unless they had specifically "opted out" of the donor system during their lifetime. Close family members would still have the right to refuse permission for the organs to be removed.
But the Bishop of Birmingham, the Rt Rev David Urquhart, warned that organ donation was a sensitive issue - and suggested it would be wrong to assume anyone had given permission for their organs to be used.
He said: "Organ donation is an extremely sensitive area for many people.
"I would support an extensive 'opt-in' campaign which encourages people to sign up as donors and builds on the
advertising and marketing of the last decade or so.
"I have carried a donation card for a number of years and hope my organs might be used to give life and strength to someone else.
"We know that a shortage of donors leads to tragedy and suffering as people wait for vital transplants and I would want to support and encourage any initiative that increased the number of consenting donors of organs."
He added: "However, this kind of generosity should not be assumed or demanded. After someone has died the body can be important for those left and I hope this debate will encourage families and colleagues to reflect in advance on the implications of the death of a loved one including the possibility of organ donation."
Mr Johnson said the Government's Organ Donation Taskforce had recommended a series of reforms to increase the number of donors, including employing 100 extra transplant co-ordinators to work with hospitals.