Germany's constitutional court has been handed a second complaint over the EU's Lisbon Treaty with the potential to delay the country's final ratification of the document for several months.
The new legal action, running to over 200 pages, is concerned with economic as well as political issues, which the complainants say are not addressed by the Lisbon Treaty.
The Lisbon Treaty was signed by EU leaders in late 2007 (Photo: Portuguese EU Presidency)
They argue that a prognosis on European integration given by the country's constitutional court in a 1993 judgement on the Maastricht Treaty - which paved the way to the euro - has turned out to be false.
Instead, EU integration has been characterised by "continuous breaches of the stability pact, a presumptuous over-stepping of power by the European Commission, unaccountable leadership and dissolution of the separation of powers," say the authors in a statement on Monday(26 January), according to German daily Frankfurter Allgemeine Zeitung.
They say that the constitutional court cannot approve the Lisbon treaty because it "strengthens the current practice of dismembering the division of powers and mixing of competences."
The complaint is being brought by Markus Kerber, a commercial lawyer, Dieter Spethmann, a former chief executive of Thyssen, former MEP Franz Ludwig Graf Stauffenberg and economist Joachim Starbatty.
Germany's highest court is already dealing with a separate complaint on the Lisbon treaty by conservative MP Peter Gauweiler. It is due to have a two-day hearing on his complaint - which says the treaty undermines freedoms guaranteed in the German constitution - on 10 and 11 February.
But the latest complainants have refused to take part in that hearing, reports Handelsblatt newspaper, wanting to have their argumentation proofed separately by the court.
The court now has to decide whether it will accept to proof their case. If it does, it is likely to take several months to come to a decision.
This could delay the German government's timetable for the treaty, which it would like in place across the bloc by the end of the year.
To go into force, the charter still needs to be accepted by Irish citizens, due to have their say in a second referendum later this year and be ratified in the Czech Republic. Meanwhile, Poland's president Lech Kaczynski has said he will only formally approve the treaty if Ireland says Yes in autumn.
For its part, Germany has to hand the papers of the Lisbon treaty over in Rome for complete ratification to have taken place. The president, Horst Koehler, is waiting for the court judgement before making the move.