The master of a seagoing vessel flying the national flag of Estonia and engaged in domestic voyages or regular service from an Estonian port may only be an Estonian citizen, an EEA citizen or a citizen of a state which grants a similar right to citizens of Estonia by an international agreement.Article 4(3) of the Regulation 2017/352 allows MS to give preferences to local suppliers for port-related activities in case it is necessary to respect the national Labour law. 