At least two Turkish air force F-16s buzzed the "Green Line" in the Greek-Cypriot quarter of Ayios Andreas in Nicosia yesterday on their way to the Turkish airbase at Lefkoniko.
Six Turkish jets landed to match the four mainland Greek F16s and two C-130 Hercules transport planes which spent a dozen hours on the tarmac at a Greek-Cypriot military airfield on Tuesday and Wednesday.
Greece warned Turkey that the dispatch of warplanes to Turkish-occupied parts of Cyprus was "completely illegal".
"Turkey already has a plethora of illegal arms on Cypriot soil," the Greek Foreign Minister, Mr Theodoros Pangalos, said in Athens. Sending these planes "changes nothing for the current situation".
The Greek government spokesman, Mr Dimitris Reppas, said: "Turkey's attitude does not help in finding a solution to the Cyprus problem."
Asked if Greece would send further jet fighters to the island, Mr Reppas would only say: "Questions about the defence of Cyprus are dealt with by the Cypriot government. It alone makes decisions about its defence."
The Turkish-Cypriots and Turkey, in turn, described the earlier brief passage through Cypriot airspace by the Greek aircraft as "provocative". Responding to Turkish protests, the Cypriot Minister of Defence, Mr Yiannakis Omirou, said the Greek landings proved "the base is operationally ready" and that the defence pact with Greece is "a reality" which must be taken into consideration by Turkey.
The visit to the island by mainland Greek planes coincided with calls by several Turkish warships at the ports of Famagusta and Kyrenia in the north. But yesterday's show of force by Turkey was meant to make the point that Ankara is better positioned than Athens to win the game of tit-for-tat.
Cyprus government reaction to yesterday's land and sea manoeuvres was to say that they only underscored the need to "demilitarise the entire island". The display of solidarity with Cyprus by the Greek air force followed the seizure on Sunday by Turkish customs of seven mobile missile launchers aboard a Maltese-registered cargo ship stopped and searched at the mouth of the Dardanelles Strait, linking the Black Sea to the Mediterranean.
The Turks suspected that the ship could be carrying to Cyprus components of a Russian S-300 missile air defence system, which the Turkish military has threatened to "take out" either en route to the island or after its installation round the Paphos airfield.
While these two events heightened tension on the divided island and put pressure on international mediators to solve the Cyprus problem, the landings and seizures were part of a protracted and dangerous game Cypriots from both communities, Greece and Turkey, the US, Russia and Europe are playing.
This game began in January 1997, when the Greek-Cypriots announced that they had ordered two batteries of S-300 ground-to-air missiles (40 in number) to protect the republic's only military airfield, at Paphos on the west coast, from Turkish attack. Although Turkey did nothing when the republic advertised that it had acquired French Exocet anti-ship missiles in 1995, Ankara responded promptly to the missile deal with warnings not to proceed with delivery.
But the Turkish general staff did not, in fact, take the missiles very seriously. While the Defence Minister, Gen Ismet Sezgin, warned that Turkey would "do whatever is necessary" if the missiles were deployed, he also said that attacking Turkish forces would be delayed "only 10 minutes" by these weapons and they would not change the balance of power on the island.
The US and Britain take the Turkish warnings seriously and have appealed to the Greek-Cypriots to cancel the order or suspend delivery of the system. The Greek-Cypriots have repeatedly offered to do so if there is significant progress towards the reunification of the island through UN-mediated negotiations for a bizonal, bicommunal, demilitarised federation.
Moscow pledged to protect the missiles until they are installed and supported the Greek-Cypriot stand on a negotiated settlement - until last Saturday, when an anonymous Russian diplomat based in Ankara said the missile deal could be scrapped if Turkey ordered $5 billion worth of tanks from Russia. This was the first time Moscow indicated that it could cancel the Cyprus deal on commercial grounds.
Meanwhile, the Russian weapons exporter Rosvooruzheniye denied that the Maltese ship was carrying S-300 components and said the missiles would be delivered between mid-July and mid-August - by Russian military aircraft if necessary.
Eager to avoid a crisis at the height of the tourist season, Greek-Cypriot sources have suggested a date in October and the Greek Foreign Minister, Mr Theodoros Pangalos, said the weapons would not be delivered until November, leaving four to five months for reconsideration.