3. To the extent that the air navigation service provider has reasonable means to mitigate the impact of external factors, where performance targets contained in the performance plans are not reached or the performance plan is not correctly implemented, the national supervisory authority shall require corrective measures to be implemented by the air navigation service providers concerned. Those corrective measures shall be adequate to improve the performance and proportionate, in particular considering interdependencies with safety and between performance areas, and the impact on the network.
Where corrective measures imposed are not properly applied, the Member State concerned shall take appropriate measures and inform the Commission. In the event of persisting underperformance, the Commission may take action in accordance with Article 34(2) and 34(3).