By FIONA MACRAE

Last updated at 10:43 16 July 2007

Doctors should have the right to remove a person's organs after death unless they have explicitly asked for them not to be taken, Britain's top medical adviser willl recommend this week.

Sir Liam Donaldson is expected to call for the law to be changed to introduce a system of organ donation that presumes consent.

It is thought that the change from the current system, which relies on people stating they wish to be donors, will free up hundreds of hearts, kidneys, livers and other organs for transplant each year.

Currently just a quarter of the population are members of the organ donor register - and around 400 people die a year while waiting for a transplant.

However, while such a change would save lives, it would prove controversial, with critics questioning the need to give the state new powers over people's bodies.

Sir Liam, Britain's chief medical officer, is expected to call for the system to be changed when he publishes his annual report on the nation's health.

A change to an opt-out system already has the support of the British Medical Association.

A recent BMA report states: 'Each year, many people die waiting for organ transplant.

'At the same time, bodies are buried or cremated complete with organs that could have been used to save lives, not because the deceased objected to organ donation but simply because they never got round to signing up to the NHS Organ Donor Register or informing their relatives of their wishes.'

The BMA favours a 'soft' opt-out system, under which family members would still have the right to veto donation. Similar systems already operate in Spain and in Belgium, where the number of organs available has almost doubled.

However, such as system is not a universal success, with Sweden having a lower rate of donated organs than the UK, despite having an opt-out law.

Just 14.4million Britons are registered as donors, however studies suggest that up to 60 per cent support a move to presumed consent.

Dr Vivian Nathanson, the BMA's head of science and ethics believes Britons are becoming ready to accept such a system.

She said: 'We are now getting close to a system of presumed consent. We have exhausted all other ways of increasing the number of organs available but people are still dying on the waiting list and that is making us more courageous.'

A spokesman for UK Transplant, which runs the organ donor register, said: 'We welcome any debate that raises the value and importance of transplantation and increases the general public's knowledge of the importance of organ and tissue donation.'