Passerelle clause

A passerelle clause is a clause in treaties of the European Union that allows the alteration of a legislative procedure without a formal amendment of the treaties. The use of a passerelle clause required unanimity of all member states although member states with opt-outs and those not participating in an area under enhanced cooperation may not have a vote. Unlike formal treaty revision their use does not require national ratification. Passerelle is French for a small bridge.

As of the coming into force of the Treaty of Lisbon, there are two general passerelle clause which apply to all decision making under the treaties. They are subject to the following preconditions:

Provided the preconditions are met, the European Council acting unanimously can:

There are a further six specific clauses. These apply to specific policy areas and may be easier to adopt that the general clauses as they require fewer preconditions. In four of them it is the Council of Ministers rather than the European Council which may the decision to use the clause. The European Parliament has no role in four of the clauses and is limited to being consulted in the other two. A national parliamentary veto is only retained in one of them.

...
Wikipedia