While breakthroughs so far have been made by researchers working with blood cells, no significant achievements have yet been made in finding cures for killer diseases such as diabetes, Parkinson's and Alzheimer's.

Research teams have also generally been small, in size and focus, and limited to a few countries where finance for such work is available - the US, Britain, Australia, China, Singapore and South Korea. The field was limited further in 2001, when US President George W. Bush banned federally funded laboratories from doing work that involved the creation of any type of human embryo.

That was the impetus for Dr Pedersen, an American, to move to Cambridge University from the University of California in San Francisco. Britain was the first country to authorise the cloning of human embryos to produce stem cells for research. It also boasts the world's first human stem cell bank.

Although Britain has strict legal safeguards in place for such work, Dr Pedersen considers the environment ideal to deliver clinical benefits as soon as possible. 'We have freedom to operate here,' the 59-year-old scientist said from his office this week. 'We can take the work all the way to the clinic. There are no constraints other than the rather strict regulatory framework that exists in the United Kingdom. But there are no political restraints on the work - it, rather than the politics, leads the way.'

Mr Bush's aversion to research with embryonic and cloned human stem cells is based on pro-life religious arguments centred on foetal development. The contention is that using such cells for research is, in effect, murder.

Senator John Kerry, Mr Bush's challenger for the US presidency in November's elections, recognised the constraints being put on American research during a campaign speech in the state of Colorado last month. The Democratic Party candidate had just won the endorsement of 48 Nobel Prize-winning scientists who accused Mr Bush of 'compromising our future'.

'We need a president who will again embrace the tradition of looking towards the future and new discoveries with hope based on scientific facts, not fear,' Mr Kerry said, outlining plans to lift American barriers to stem cell research.

Dr Pedersen described the move as 'admirable', although he did not believe it would lead to a long-term shift in US policy on research on human stem cells. 'One of the problems for the US that cannot be undone is the volatility of the policy and its susceptibility to a political outcome,' he said. 'That has not seemed to be the case in the UK. It has a stable, well-articulated, well-accepted policy in support of stem cell research.'

He also praised stem cell work being done in Asia, particularly China, Singapore, South Korea and Australia, which he described as 'a part of the world to watch very closely for major contributions'.

Scientists know little about stem cell research taking place in China. The few papers published by Chinese scientists in English-language journals - the internationally recognised method of announcing breakthrough - have spoken of wide-ranging work in all areas.

Research work at Singapore's Biopolis scientific park is much better documented. Doctors there recently announced they had successfully transplanted umbilical cord stem cell blood to a 17-year-old boy suffering from a genetic disease that made him susceptible to severe infections. But Dr Pedersen saw such work as competitive only in the sense that scientists were vying for prominence.

'Researchers worldwide are all involved in an international undertaking and are seeking to do it co-operatively with other countries,' he said. 'No single country can do this by themselves, so it is important for us to use an international model such as the Genome Project so that we can achieve this in the shortest possible time.'

The Cambridge effort was geared to that aim, he said. Drawing together 200 scientists in the university and a further 50 hired researchers into six core groups and about 20 other affiliated teams, the centre would be ideally positioned to seek cures.

The two areas of research would be basic stem cell biology and the study of clinically useful cell types. Mammalian, as well as human cell systems, would be studied.

Clinical research would focus on afflictions associated with the brain, specifically diabetes and Parkinson's disease. 'We've chosen these two disease areas because they could possibly be treated with a single, purified cell type,' he said. 'These have been picked because they're realisable targets.'

He believed that finding cures for diabetes and Parkinson's would provide a path to tackling other diseases. With these resources, there was a high probability of success in a matter of years after achieving the initial aims.

Dr Pedersen spoke with the zeal of someone on a mission. With such resolve, his goals - although unreachable now - could soon be within his grasp.