Member States shall ensure that all customers connected tothe gas network are entitled to have their gas provided by a supplier, subject to the supplier’s agreement, regardless of the Member State in which the supplier is registered, as long as the supplierfollows the applicable trading and balancing rules and subject tosecurity of supply requirements. In this regard, Member Statesshall take all measures necessary to ensure that administrativeprocedures do not constitute a barrier for supply undertakingsalready registered in another Member State.
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