the carriage of passengers or goods by sea between: - ports situated on the mainland and on one or more of the islands of one and the same Member State, - ports situated on the islands of one and the same Member State; Ceuta and Melilla shall be treated in the same way as island ports., the carriage of passengers or goods by sea between/ports situated on the mainland and on one or more of the islands of one and the same Member State/ports situated on the islands of one and the same Member State