Open access journals charge researchers a fee for publishing their research rather than the subscriptions that traditional journals charge readers.

The debate over open access is raging on both sides of the Atlantic, driven by the argument that science funded by governments and charities should not sit behind a pay-wall and generate huge profits for private companies.

The next battleground will be the EU's planned 80 billion euro research funding program known as Horizon 2020. It will award grants for research projects running for six years from 2014.

The UK government will be out on a limb in its support for open access unless the EU and, even more importantly, the United States fall in behind it.

"If the EU puts in an open access mandate then it's the whole of Europe and the game is won," said one source close to the issue.

Universities and Science Minister David Willetts on Monday said the funds to support the transition to open access in the UK will have to come from the existing UK science budget of 4.6 billion pounds.

In the long term, the government would like to see a wholesale shift to open access but during the transition period universities will have to shoulder both the costs of subscribing to important academic journals and the charges levied on its researchers to publish in open access media.

The government's failure to find new money to fund the transition to open access has sparked fears that there will inevitably be less money for the research itself.

"We are concerned that these transitional costs appear set to fall on the science budget, reducing the funding available for UK researchers to carry on the work that has put this country at the forefront of many fields, including physics," said Sir Peter Knight, president of the UK's Institute of Physics.

Willetts believes the extra 50-60 million pounds needed to support publication charges can be found in efficiency savings in other areas of university funding but he predicted the benefits of a shift to open access will outweigh any short-term pain.

"It will allow academics and businesses to develop and commercialize their research more easily and herald a new era of academic discovery," the minister said in a statement.

But Dame Janet Finch, who headed the group that produced the government-commissioned report, argued the economic benefits of easier access to research warrant extra investment.

"Although I recognize that we are in a period of financial stringency, the government has endorsed the huge economic potential of this move," said Finch in a statement. "I therefore hope that this will be taken into account in the next round of funding allocations to research funders and to universities."

Academic publishers like Reed Elsevier PLC, Springer Science + Business Media and Macmillan's Nature Publishing Group, will continue to earn revenue under either model. All of them have a number of open access options in their stable of journals.

The big unknown is the impact on research funding if there is a wholesale shift to open access that includes premier journals like Nature, Science and Cell.

While charges for publication in existing open access media average about 2,000 pounds per research paper, Nature has already estimated it would have to charge in excess of 10,000 pounds to maintain revenues if it abandoned subscriptions.

(Editing by David Cowell)

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