As if to remind the world of the geopolitical implications of a Greek exit from the eurozone, Turkey on Thursday said it had scrambled military jets earlier in the week to intercept an Israeli plane that violated northern Cypriot airspace.

Monday’s reported incursion coincides with mounting tensions on the Mediterranean island over oil and natural gas exploration plans there. Turkey previously condemned the Greek-speaking south when it announced plans to drill for natural resources off Cyprus’ coasts but has since endorsed similar plans on the part of the Turkish government in the north which only Turkey recognizes.

Athens naturally supports Greek Cyprus in its energy and political disputes with Turkey and has signed mutual defense guarantees with Israel following the Israeli-Turkish rift.

Relations between Ankara and Jerusalem soured when Israeli commandos raided a Turkish vessel that was bound for Gaza in May 2010 and killed nine Turkish activists on board.

Cyprus has been divided since 1974 when the Turkish military invaded the island after a short-lived Greek Cypriot coup engineered by the military junta then in power in Athens.

Turkey still keeps some 30,000 troops in the north while a buffer zones that separates the two sides is monitored by the United Nations. Greek-Turkish relations have been strained ever since Greece won its independence from the Ottoman Empire in 1821. Maritime border disputes between the two nations in the Aegean Sea are unresolved to this very day.

Israel’s support of Greek Cypriot exploration efforts complicates the picture. As analysts from the geostrategic consultancy firm Wikistrat pointed out in February, “While Israel views Cyprus as the best and most direct way to transfer gas to Europe, Turkey will view this as a way to undermine Turkish Cypriot interests.”

If Greece is forced to leave Europe’s single-currency union and possibly suffers a bankruptcy, its Cypriot allies would necessarily lean more heavily on their newfound friends in Israel. Moreover, there is a good chance that Russia will step in to take advantage of the situation.

As the Financial Times explains, the damage to Cyprus’ financial system, heavily exposed to Greek debt, would be devastating if the nation left the euro.

Cyprus last year received a cheap €2.5 billion loan from Russia in a gesture that reflected the Kremlin’s interest in protecting wealthy Russian depositors with billions parked in Cypriot banks. It may soon need more aid.

The links between Greece and Russia have historically been strong, writes Walter Russell Mead at The American Interest.

In Ottoman times, Orthodox Russia was the protector of Orthodox Christians in the great Islamic empire and frequently used its diplomatic clout to defend the rights of its coreligionists. Greece looked to Russia as a reliable ally during much of the troubled period after modern Greece gained independence from the Turks.

If Greece feels abandoned by its European partners, it may look to Moscow for shelter again. That would leave Europe without a foothold in the eastern Mediterranean.

Turkey is formally still engaged in European Union membership talks but the prospect of it joining the union any time soon is dim indeed.

Cyprus is in the euro but would likely require financial support if Greece collapsed, raising the question of whether it wants to submit to the very austerity measures that doomed Greece or seek its future elsewhere.

Israel has a clear interest in balancing against what it perceives as Turkish hostility and will be quite willing to strengthen ties with both Cyprus and Greece.

Russia could finally attain what Greek and Turkish NATO membership was supposed to deny it — unfettered access to the eastern Mediterranean Sea for its navy.