With summit conclusions almost entirely agreed in advance, EU leaders are meeting to formalise their agreement on two major topics.
First of these is "limited treaty change" desired by Germany to put in place a permanent rescue mechanism for the euro zone, under strict policy conditions. Heavily indebted countries, such as Greece and Ireland, would be able turn to it as a last resort and by unanimous vote.
In practical terms, a simple sentence would be added to Article 136 of the Treaty on the Functioning of the European Union.
The sentence would read: "The member states whose currency is the euro may establish a stability mechanism to safeguard the stability of the euro area as a whole. The granting of financial assistance under the mechanism will be made subject to strict conditionality."
Member states will be able to avoid ratification by public referenda because the treaty change is considered "limited" and falls under the category of "simplified revision procedures" in Article 48.6 of the Lisbon Treaty.
Still, all 27 member states must ratify the changes in their national legislatures.
Countries that do not use the euro, such as the United Kingdom and Sweden, would not be liable for any financial impact on the EU's budget and would not vote in deciding when to put the mechanism into action.
The final details will be fine-tuned by finance ministers before a European Council summit next March. The ratification process in the 27 countries could then start and should be concluded by the end of 2012, meaning that the mechanism would enter into force on 1 January 2013.
The new crisis mechanism will be closely modelled on the temporary fund used to bailout Greece and Ireland. Provisions for that fund expire in mid-2013.
No euro bonds in the deal
The financial arrangement, however, is not expected to include eurobonds, because that would be considered a "permanent" exception to the rule that countries must not cover each other's debts.
The second issue to be discussed by leaders could prove more difficult to resolve. In a nutshell, heads of state and government need to decide how the new mechanism will be triggered, how it will be financed, whether there will be a role for financial markets, etc. On these problems, an agreement is not expected until next April, with its possible adoption in June.
Will budget talks steal the show?
Reportedly, most leaders want to avoid a repetition of the October summit, when UK Prime Minister David Cameron abruptly introduced the issue of the 2011 budget. This time, it is feared that the issue of the longer-term budget could steal the show.
The long-term EU budget for the period 2014-2020 is not on the agenda and Van Rompuy has reportedly conveyed the message that any country that raises it would gravely offend the Commission.
A diplomat told EurActiv recently that discussions should not start until the Commission has tabled its own proposals in June 2011. Otherwise, the message would be that the Commission was taking orders from member states.
"This summit is very well prepared. Van Rompuy has engaged himself and his team in very active political consultations," a high-ranking diplomat said.
He cited as an example pension reform, where a compromise was found in a "remarkable" manner before the summit, in his words, thanks to Van Rompuy's skills.
Diplomats also expressed hope that "any last minute innovative ideas" would not complicate the summit. Mulling the introduction of eurobonds or own resources is widely considered "not timely".