Greece has not yet claimed an exclusive economic zone, although it is entitled to do so, as per UNCLOS 1982 as well as customary international law. The reason for its inaction is the direct Turkish threat of casus belli.

Turkey's declaration of casus belli is not related to the EEZ issue. Aegean Sea is a semi-closed sea which has a special nature. Moreover, Turkey is not among the signatories of UNCLOS which allows countries to expand width of their territorial waters up to 12 nautical miles. Besides, Turkey is a persistent objector to the relevant article of UNCLOS. In 1995, just after Greece's ratification of UNCLOS, Turkey declared that if Greece expands the width of her territorial waters over 6 nautical miles (e.g. 12 nautical miles), Turkey would conceive this action as a containment attempt and a direct offence to her sovereignty. So, Turkish Parliament decided that if Greece attempts to expand the width of her territorial waters it would be a cause of war (casus belli). 
EEZ problem -which is waiting for a viable solution- is just another problem between Turkey and Greece besides other problems.


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