16. Arrangements ensuring legal certainty and equal treatment should be found for all court procedures pending before the Court of Justice of the European Union upon the date of withdrawal that involve the United Kingdom or natural or legal persons in the United Kingdom. The Court of Justice of the European Union should remain competent to adjudicate in these procedures. Similarly, arrangements should be found for administrative procedures pending before the European Commission and Union agencies upon the date of the withdrawal that involve the United Kingdom or natural or legal persons in the United Kingdom. In addition, arrangements should be foreseen for the possibility of administrative or court proceedings to be initiated post-exit for facts that have occurred before the withdrawal date.