Urbanization leads to the creation of global cities which are assessed not only by their size but also innovative capacity, networking, inhabitants’ activity or quality of life. Global cities emerge as the separate actors of international relations. Therefore, their authorities are more and more prone to conduct foreign policy on city-tocity and city-to-state levels which is acknowledged by the subjects traditionally responsible for the foreign policy. This leads to the change in the practice of diplomacy where local authorities are perceived as equal partners.