Spencer Abraham, the US energy secretary, seems to have a preference over which European nation — France or Spain — should apply to host the proposed ITER fusion reactor. Not surprisingly, perhaps, given Spain's support for the Bush Administration's war on Iraq, and France's opposition, it is the Spanish bid that he has been talking up.

By the end of this year, the ITER partners are expected to make a decision on where to build the world's next magnetic-confinement fusion device, which would explore the behaviour of superheated hydrogen ions over long enough periods to infer how they might act in a fusion-based power plant. There are four proposed sites: one in Japan, two in Europe and one in Canada.

Most eyes are turned to the two parties whose money has sustained the project so far: Japan and the European Union (EU). Russia is a long-standing partner, but can't afford to offer a site, and certainly isn't planning to advise Europe and Japan on its preference. Canada has offered a site in Ontario, but although its selection would suit participating researchers in the neighbouring United States, US officials have never spoken out in favour of the Canadian site. They must realize that such a public statement of support, from a nation that has only just decided to rejoin the project and is planning to contribute no more than 10% of its US$5-billion costs, would be inappropriate.

This helps to explain why Abraham's comments, made on a visit to Madrid earlier this month, are causing some disquiet. He came perilously close to expressing US support for the Spanish bid to host ITER (see page 211). This is liable to offend the French government, as Abraham well knows.

France is one of the strongest European supporters of magnetic-confinement fusion research in general, and of ITER in particular. Its Atomic Energy Commission has the technical and managerial expertise to take a leading role in the project, so the French bid is a very serious contender. Spain, meanwhile, also has a solid bid, and can argue to that its relatively young democracy, and less-well-developed physics community, means that it has more to gain from hosting such a prestigious international project.

Abraham could remove the sour taste left by his comments in Madrid by stating unequivocally that the choice of a European site for ITER is a matter for the EU. This would prevent the project being sucked into the vortex of recrimination created by the current US administration's self-avowed intention to punish France for having the gall to oppose its invasion of Iraq.

But even if Abraham declines to make such a statement, the EU can defuse the issue. Earlier this week, ministers from its member states agreed that the EU must soon come down in favour of just one of the European sites. If the project's European partners can make a clear choice between its two bidders before the final site selection is made, Abraham's untimely intervention will be moot.