The European Commission is facing controversy over plans to change existing rules and allow member states to provide direct state aid to nuclear power.
The plans leaked to the German newspaper Sueddeutsche Zeitung and seen by Energydesk are fiercely opposed by some member states including Germany and Austria.
The proposals, drawn up by the EU’s Competition Commission could also be opposed by the influential German Energy Commissioner Günther Oettinger.
In a section, marked in italics because it may be deleted the commission spells out the criteria it would apply before allowing a member state to offer state aid for nuclear power.
In a submission to the European Commission the German Government described an earlier draft of the plans as "not acceptable".
The problem - for Germany - is that the plans would put new renewable technologies at a disadvantage by putting them on an equal footing with older, established technologies.
"On the basis of current knowledge, the German government sees no need for economic support of nuclear power. We believe it is important that different technologies be treated differently ."
The government submission also raised concerns over wider costs of nuclear power, such as the liability for accidents, suggesting it is hard to fully quantify these in any state support.
Germany is committed to phasing out its nuclear power plants and wants to get all of its power from renewable sources by 2050 and the leak is likely to become an issue in the forthcoming elections.
It is understood the draft proposals were not due to be published until after the vote.
However the plans are likely to be strongly supported by the UK and France.
Any deal between the UK government and French state owned firm EDF for a new nuclear plant is likely to classify as state aid and require approval from Brussels.
The requirement reflects the likely cost of nuclear power compared to the wholesale cost of electricity.
Even if the guidelines pass the UK may struggle to show any deal with EDF was subject to a transparent and competitive tender - as suggested in the draft document.