In Greee the term Belomorska became known between 1941-1944 when the territories of Eastern Macedonia and Thrace (Minus Alexandroupolis) was under “Bulgarian administration” on assignment of Germans, who were the ones that essenially captured it. That term which is being translated in Greek as «Aegean Administration” or “Aigaeis” was being used by Bulgarians with aim to indicate on one hand this area geographically but on the other hand as an administrative district of Bulgaria, in the sense which was given by Bulgaria and was applied in the particular historical coincidence. These terms are in use in the translation of some Administrative and Juridical decisions of the Bulgarian State and form a translation of the Bulgarian term Belomorie. 
This term is a successive situation of the broader geographically Bulgarian Term Εgeiska Makedonia (Μακεδονία του Αιγαίου), which covers the entire part of Greek Macedonia while after the war it is applied by the intellectual and political leadership of FYROM. The Term Belomorie was invented by the Bulgarian scientists/geographers of the war Period in order to attribute the geographical area between Thermaic gulf and the gulf of Alexandroupolis, corresponding to the other 2 areas that Bulgaria “occupied” during this period- Dobroutsa and the area of South Jugoslavia which had also distinct names. In the aftermath it was reduced under circumustances to define the specific area between the river Strymon and the line Alexandroupolis-Svilengrand. 
So it is sorted out the attempt of the Bulgarian Political and Intellectual leadership to familiarize the Bulgarian population to the capabilities and circumustances, by redefining geographically and linguistically the contemporary Bulgarian “historical and national Irredentist homelands”. Today the Bulgarians were substistuted by the «Makedonskiot nacionalnosti» of FYROM.
So we witness the Skopjan activists (who also advertise the ”Liberal Alliance” - “Φιλελεύθερη Συμμαχία” whenever they can) are using anymore openly, terms that naturally remind the Bulgarian occupation in Greece and the Bulgarian gangs, of Ochrana Style that went all over Macedonia and murdered brutally Greeks under the shield of German Nazism but also Italian Fascism.
As a matter of fact, is the “Liberal alliance” aware that some of its members are using such Ultra-Nationalistic Administrative Definitions in order to promote their expansionistic Propaganda??
-Η βουλγαρική κατοχή στην Αν. Μακεδονία και Θράκη (1941-1944), Ξανθίππη Κοτζαγεώργη-Ζυμάρη,2002, ΙΜΧΑ, σελ 14
- D. Jaranov, «Balgarskoto Belomorie kato geografsko poniatie» (The Bulgarian “Aigaeis” as a geographical term), Belomorski pregled 1942, n. 1, 1-10
Great thanks to history-of-macedonia.com for the translation.