If you state in a job advert that those who apply for a position must have a valid work permit or are EEA citizens, is this discrimination?

On first glance it would seem to be directly discriminatory to require that an individual be of a particular nationality in order to be eligible for a certain position. However, as outlined on the website of the Department of Jobs, Enterprise and Innovation, the Irish government's policy (as part of its obligations under the Community Preference principles of membership of the EU) is that employment opportunities that arise in Ireland should in the first instance be offered to suitably skilled Irish and other EEA nationals. Such roles should only be offered to non-EEA nationals where no suitable candidate emerges from within the EEA to fill the vacancy. This idea of Community Preference has