Revising the European treaties is a long and difficult procedure. This is to be expected, considering that revisions made can profoundly change the structure and functioning of the European institutions, and the way decisions are made in the european Union. All parts of the treaties can be changed through the ordinary revision procedure.
In short the ordinary revision procedure proceeds as follows: if the majority of the European Council agrees that one or both of the treaties require changing a Convention is convened. If the changes needed are not drastic an intergovernmental conference is called without a Convention. If the Convention or intergovernmental conference reach an agreement on changes to the treaties each member state must approve of the changes.
If the proposed changes to the treaties only affect certain policy areas the simplified revision procedure might be used.
Step 1: initiative
The goverment of any Member State, the European Parliament or the European Commission may submit a proposal to the Council of Ministers to amend the European treaties. The Council, in turn, submits the proposal to the European Council and notifies the national Parliaments.
Step 2: proposal is considered by the convention
After consulting the European Parliament and the Commission, the European Council decides, by simple majority voting, whether to take the proposal in consideration or not.
Negotiations on the proposed treaty amendment(s) are conducted by a Convention, composed of representatives of the national parliaments, the European Council, the European Parliament and the European Commission. If the proposal concerns institutional changes in the field of monetary policy the European Central Bank is consulted.
The Convention decides, by consensus, to submit the final proposal to an Intergovernmental Conference.
Step 3: approval
The Intergovernmental Conference has to approve of the proposed amendment(s) to the treaties by consent.
Finally, each member state separately has to approve the proposed treaty amendment(s).
Shortened revision procedure
This variant of the ordinary revision procedure follows the same route as described above, but skips most of step two.
When the Council of Ministers submits a proposal to the European Council, the European Council may decide by a majority vote that a Convention is not needed, but only if the proposed amendments do not significantly reform the EU treaties. Instead, the Council submits the proposal to the Intergovernmental Conference directly.
All parts of the European Treaties can be amended by the shortened revision procedure.
The ordinary revision procedure is based on the Treaty on European Union.
-procedure and application: TEU title VI art. 48 i part 1-5