The question of whether Europe should commit itself to a binding goal on renewable energy is set to dominate EU summit discussions on climate change, with the German EU presidency also putting broader energy issues, bureaucracy-cutting and the Union's 50th birthday declaration on the agenda.
EU leaders are gearing up for their yearly spring gathering on Thursday and Friday (8-9 March), which will almost certainly be the last formal summit attended by colourful summit participant Jacques Chirac of France who is expected to leave office in May.
The French president, who raised eyebrows in March last year by storming out of the summit because a French business lobbyist spoke in English, is not expected to have a quiet final appearance at Thursday's summit.
Mr Chirac is leading opposition against a key renewable energy target proposed by the European Commission, which wants EU leaders to commit themselves to have 20 percent of energy consumption produced from sources like wind and solar energy by 2020.
Both Brussels and Berlin see it as crucial that the target should be binding for Europe to maintain its credibility on the world stage, with German chancellor Merkel stating on the eve of the summit that "I think the more we are able to set a good example, the more we can convince others."
But France, Poland and a group of other new member states are strongly resisting mandatory targets.
Paris wants greater recognition of its own nuclear energy production - which it says is already "low carbon" and contributing to the fight against global warming - while post-communist EU states argue the 20 percent renewables goal is impossible to achieve for their economies which still need to catch up with the West.
EU diplomats have said one possible compromise would be an explicit mention in the conclusions of the need for fair "burden sharing" between member states, as any reduction on the 20 percent target would be seen as a painful defeat for Europe's green credentials.
ENERGY ISSUES FUDGEDMeanwhile, EU leaders are expected to endorse a goal of a 30 percent cut in CO2 emissions in the industrialised world by 2020.
Even if no agreement on the goal is reached with partners such as the US, "the EU makes a firm independent commitment to achieve at least a 20% reduction of greenhouse gas emissions by 2020 compared to 1990," according to draft summit conclusions.
But the summit is set to postpone the key political battle - over individual commitments on CO2 emissions by member states - to a later date, with the conclusions inviting the commission to propose "technical" criteria for the thorny burden-sharing question.
Another question likely to cause a tussle is how to boost the EU's heavily fragmented internal market for energy, which currently sees most member states strongly regulating and protecting domestic energy producers.
In the run-up to the summit the commission has been pressing governments to "unbundle" their big energy concerns - separating supply and distribution.
But the summit is likely to merely invite the commission to provide "additional clarifications" for a June meeting of energy ministers - a move which effectively shifts the issue back to a lower political level, according to some observers.
BUREAUCRACYAlthough the summit will be dominated by green and energy issues, some other topics of particular importance to Ms Merkel are also on the agenda.
The chancellor is expected to receive backing for her crusade against EU bureaucracy, with the conclusions saying that "administrative burdens arising from EU legislation should be reduced by 25% by 2012."
Last-minute pressure from Brussels to have national governments subscribe to a similar goal will however "not fly," according to diplomats.
Germany is also likely to get support for its idea to boost economic integration with the US through a "New Transatlantic Economic Partnership."
BERLIN DECLARATIONBut one of Ms Merkel's real political tests at the summit concerns the EU's 50th anniversary declaration to be signed by EU leaders on 25 March.
The chancellor is set to outline her ideas for the so-called Berlin declaration to her EU counterparts during Thursday's dinner, with late Thursday night press conferences by EU leaders expected to reveal some aspects of Berlin's thinking which has largely been kept under wraps so far.
The EU birthday document has sparked a broad discussion among member states who each have particular sensitivities with the declaration, including on how the document should mention the EU's institutional deadlock.
Finally, the summit is also set to see its fair share of unscheduled discussion - notably on controversial plans by the US to build an anti-missile shield in Poland and the Czech Republic, seen by some member states as unnecessarily antagonising Russia.
"It is not on the agenda but nobody can exclude that it will not come up," said diplomats.