Upset that the United States essentially sided with Turkey's assertions that parts of the Aegean and East Mediterranean aren't officially delineated, Greek diplomatic sources fired back they are Greek waters.

A US State Department report to Congress, prepared as part of the so-called East Med Act, said the waters are disputed because Greece and Turkey haven't worked out an agreement on boundaries.

That irked Greek officials, not named, who told Kathimerini that there's no question of Greek sovereignty of the waters as Turkey has sent an energy research vessel and warships off the Greek island of Kastellorizo, near Turkey's coast.

The limits of Greece’s territorial waters, as well as the maritime borders between Greece and Turkey, have been clearly defined for years on the basis of conventional and customary international law and “cannot be disputed,” diplomat sources told the paper.

“As regards the southeastern Aegean and the Eastern Mediterranean, the maritime borders have been defined by the Italy-Turkey Agreement signed in Ankara on 4 January 1932, as well as the minutes which form an integral part of this deal which were signed on December 28, 1932,” they added.

“Greece, as the successor state, under the Treaty of Paris of 1947, gained sovereignty over the Dodecanese without any change in the maritime borders, as agreed between Italy and Turkey,” the report added.

Turkey is claiming waters around Greek islands under a maritime deal with Libya that no other country recognizes, Greece countering with a similar deal with Egypt that led Turkish President Recep Tayyip Erdogan to cancel planned talks in Ankara – not Athens – with Greek officials.

The Greek Navy is shadowing Turkish warships protecting the energy research vessel the Oruc Reis, adding to worries there could be a conflict between the NATO allies, the defense alliance failing to bring a de-confliction agreement.

The US report also wouldn't back Greece's claims to airspace over Greek territory, again trying to walk the line between Greece and Turkey. The US wants an expanded military presence in Greece but President Donald Trump said Erdogan is a friend of his and has done favors for him.

While backing Greece's claims to seas boundaries – but agreeing with Turkey they are “disputed,” – the United States isn't supporting Greece's defined air space repeatedly violated by Turkish fighter jets.

The US State Department said, it can't verify confirmed violations after Jan. 1, 2017 because there's no consensus on the air space area over Greece, according to a report to Congress prepared in the context of the East Med Act.

The report states that Greece claims an airspace that extends up to 10 nautical miles and a territorial sea of up to six nautical miles, said Kathimerini.

“Under international law, a country’s airspace coincides with its territorial sea. The US thus recognizes an airspace up to six nautical miles consistent with territorial sea. Greece and the US do not share a view on the extent of Greece’s airspace,” which essentially means the US won't back Greece over Turkish fighter jets between 6-10 miles over Greek territories and seas.

The report adds that although Athens currently claims up to a 6-nautical-mile territorial sea in the Aegean, “Greece and its neighbors have not agreed on boundary delimitation in those areas where their lawful maritime entitlements overlap,” the US trying to simultaneously please both Greece and Turkey.

“Lack of such delimitation means there is no clarity on the extent of Greece’s territorial sea and corresponding airspace in these areas rendering any assessment of total violations not feasible,” the report also said.