The core of the conflict is the persistent abuse of "Flight Information Region" (FIR) responsibility by Greece.

FIRs were devised by International Civil Aviation Organization in 1950's to provide facilities and services to the civilian aircraft in the international airspace. FIR arrangements solely entail technical responsibility. It does not change the free status of the airspace over the high seas under international law.

FIR responsibility over the Aegean international airspace was assumed in 1952 by Greece. Greece, however, deliberately misinterprets and abuses her FIR responsibility as if it entails sovereignty over international airspace. It considers FIR as a national boundary line. (i.e. Western boundary of Türkiye  and Eastern boundary of Greece, embracing all international airspace in the Aegean beyond Turkish territorial sea within Greek sovereignty area).

Likewise, Greece considers FIR as a defense perimeter. Consequently, Greece maintains the view that military aircraft entering into Athens FIR and flying in international airspace should submit flight plans and come under control of Greek air traffic control authorities.

However, Article 3/a of the ICAO Convention says “This Convention shall be applicable only to civil aircraft and shall not be applicable to state aircraft”. Therefore, military aircraft flying in international airspace is under no obligation to submit flight plans according to international law.

However, Greece claims that non-submission of flight plans by Turkish military aircraft constitutes a "violation of the Greek FIR". There is no such concept of "violation of an FIR" since FIR responsibility does not imply the recognition of sovereignty of that state over the international airspace. Greece, thus, formulates and implements unlawful positions and then complains of their violation.

Greek abuse of FIR responsibility is yet another manifestation of her claim of "de facto sovereignty" over the whole Aegean airspace.

Greek aircraft constantly intercept and harass Turkish military aircraft over the international airspace on the false pretext that they violated Athens FIR by not submitting flight plans. Greek protests on these grounds have repeatedly been rejected by Türkiye.

Another problem concerning the Aegean airspace is the Greek claim of 10 miles breadth of national airspace.

In international law, the boundary of territorial sea of a state also constitutes the boundary of its airspace.

Greece declared a 10 NM wide national airspace in 1931 even though  the width of its territorial sea was 3 NM at that time. Greece later extended its territorial waters to the present 6 NM in 1936. 

Greece’s claim of 10 NM national airspace is against the rules of international law and consequently, the airspace between Greece’s 6 NM territorial waters and its declared 10 NM national airspace is part of the international airspace.

Greece’s 6-10 NM airspace claim is not recognized internationally. Nor is it recognized by Türkiye. Most of Greece’s claims about the violation of its airspace concern the flights of the Turkish military aircraft within the 6-10 NM international airspace