Nobel laureate Sir Paul Nurse, who left Britain for New York two years ago, has launched a withering attack on the state of biomedical research in the US.
Sir Paul, one of Britain's most popular and influential Nobel prizewinners, took over as president of Rockefeller University in 2003, fuelling fears that the US was succeeding in luring away Britain's best scientific brains.
But in a paper written for the journal Cell , he has revealed his disillusionment with the American system. He warns that biomedical research is "under siege".
Countering the popular view that research money grows on trees in the US, Sir Paul says that in the past three years, science funding increases have struggled to keep pace with inflation and that the outlook is "worsening".
He also attacks the political climate, warning that political leaders are failing to take science seriously and creating an "atmosphere of fear"
The article will raise hopes that Sir Paul, who won a Nobel prize in 2001 for unravelling the genetic mechanisms that control the division of cells, could return to the UK in the near future.
He is tipped as a likely candidate to become either the Government's chief scientific adviser or the next president of The Royal Society.
Recently he has been in negotiation with a major British research university about the possibility of returning.
In his paper, Sir Paul says: "The success rate of awards compared with applications has slipped from close to one in three in the late 1990s to nearly one in five.
"This stagnation in research funding is placing great pressure on the US biomedical research enterprise."
He says that "stop-go funding" will have a negative impact on the recruitment of the next generation of scientists, which will be felt "for years to come".
The paper is also strongly critical of the political climate in the US.
Sir Paul writes: "In this atmosphere of fear, strangely reminiscent of Galileo being shown the instruments of torture because of his heliocentric views, the scientific community may begin to lose its confidence and turn on itself."
At a time when Prime Minister Tony Blair and Chancellor Gordon Brown frequently stress the importance of science to the UK economy, Sir Paul says that political leaders in the US have "little understanding of, or respect for, science".
He criticises President George W. Bush for commenting that intelligent design should be taught alongside traditional lessons about Darwinian evolution and attacks Elias Zerhouni, the president of the National Institutes of Health, for failing to take a more public stance in the fight against creationism.
He is also critical of the lack of dialogue about the controversial issue of stem-cell research in the US. NIH guidelines ban federal support for work on human embryonic stem-cell lines produced after 2001.