President Recep Tayyip Erdogan on Sunday visited the Turkish-occupied north of Cyprus at a time of heightened tensions on the divided island and in the Eastern Mediterranean.
Erdogan was to attend a "picnic" in the disputed beachfront area of Varosha along the UN buffer zone that has divided the island since Turkey's 1974 invasion of the north.
The majority Greek-speaking Republic of Cyprus, an EU member with effective control over the southern two thirds of the island, has condemned the visit as a "provocation without precedent".
Erdogan's visit comes at a time when regional power Turkey has openly sparred with neighbours Greece and Cyprus over maritime territories believed to hold vast gas deposits.
An eventual reunification of Cyprus has looked more remote since an Erdogan-backed Turkish nationalist, Ersin Tatar, was elected leader of the north last month.
The Turkish president visited on Sunday to mark the anniversary of the self-proclaimed Turkish Republic of Northern Cyprus (TRNC), which is recognised only by Ankara.
Erdogan was due to visit Varosha, a long-abandoned beach resort that was once the playground of celebrities and dubbed a "Jewel of the Mediterranean".
The Turkish invasion -- launched in response to an Athens-engineered coup in Nicosia designed to unify Cyprus with Greece -- was followed on November 15, 1983 by the declaration of the TRNC.
Since then, Varosha has been a fenced off ghost town, where former luxury hotels and restaurants have fallen into disrepair and overgrown by weeds and bushes.
Turkish troops partially reopened the seafront of Varosha on October 8, stirring international criticism.
Cyprus President Nicos Anastasiades condemned Erdogan's visit, as well as what he called the historical "secessionist act of the declaration of the illegal regime" in the north.
He said Erdogan's visit served to "torpedo" UN-led efforts to work toward resolving "the Cyprus problem" in talks between Greek and Turkish Cypriots, Athens, Ankara and former colonial power London.
Erdogan's increasingly assertive stance has sparked protests in the Greek-speaking south -- but also in the north, where many Turkish Cypriots resent Ankara's interference in the island's politics.
"No interference! Freedom for all!" hundreds of Turkish Cypriot protesters chanted in northern Nicosia on Tuesday to denounce Erdogan's visit.