Translate the following English sentence to French:
"European requirements should apply because a European railway system requires regulations at European level rather than additional regulations at national level, because the latter would enable Member States to carry out certain activities which they no longer have to do within a European market."
Tout ceci doit constituer une priorité. C'est indispensable car un réseau ferroviaire européen a besoin d'une réglementation européenne et pas d'une réglementation nationale complémentaire inutile sur un marché européen.