ATHENS - President Recep Tayyip Erdogan began a state visit to Greece on Thursday, the first by a Turkish head of state in 65 years, by needling his hosts with revisionist border talk and complaints about its treatment of Muslims.

In what he called a “historic” visit, Erdogan said Athens was neglecting the Muslim minority of Turkish origin that lives in northern Greece, and accused the European Union of ignoring promises of financial support given last year in return for Turkey’s help in stemming refugee flows.

“The European Union... has not put into effect any of the promises it gave on the economic side (whereas) we are abiding by our commitments,” Erdogan told Greek President Prokopis Pavlopoulos.

Pavlopoulos, one of the country’s foremost law experts, insisted that Greece had no intention of revising the 1923 Treaty of Lausanne, a defining document in Greek-Turkish relations, as Erdogan has repeatedly suggested.

“This treaty is non-negotiable for us... it requires no revision nor update,” he said.

Erdogan argued that agreements can be “updated” and claimed Greece was failing to adhere to the treaty regarding the Muslim minority.

Contrary to the treaty, Athens appoints religious jurists known as muftis instead of allowing the local community to do so, Erdogan said.

“Certain things must change. And protecting the rights of our fellow ethnic (Turks) is a top priority for us,” he said.

Erdogan , who visited Greece twice as prime minister in 2004 and 2010, will travel privately Friday to the northeastern region of Thrace where the Muslim minority lives.

Further souring the two-day trip, Erdogan said in an interview Wednesday that airspace and territorial borders could “be improved”.

Relations have been plagued by territorial disputes in the Aegean, with the two NATO allies nearly going to war in 1996 over uninhabited islands.

There are often confrontations when Turkish warplanes enter airspace that Greece claims as its own, prompting Greek authorities to scramble jets in response.

“Airspace and territorial waters and the different measurements can be improved,” Erdogan told Greece’s Skai TV on Wednesday.

Erdogan actually has a relatively warm relationship with Alexis Tsipras, the leftist politician who became Greek prime minister in 2015 and generally eschews nationalist rhetoric against Turkey.

But another more recent bone of contention is Greece’s failure to extradite eight Turkish officers who fled to its territory last year after allegedly participating in the attempted coup against Erdogan .

“(Tsipras) said he was going to follow up the situation, and not later than a fortnight they shall be extradited to Turkey. That was what he said. But, unfortunately, right now, they are still in Greece,” Erdogan said in Wednesday’s interview.

The Greek Supreme Court has blocked the extradition of the officers, and Erdogan lamented that taking the legal route “takes longer”.

“Terrorists, when they are detained in Greece, they should be extradited to Turkey. If you leave it in the hands of the judiciary no outcome can ever be cultivated and you won’t be able to cultivate any results,” he said. “Delayed justice is no justice.”

Tsipras appeared to try to smooth over any tensions ahead of the visit, telling Turkey’s state-run Anadolu news agency that suspected coup plotters “were not welcome” in Greece and emphasised the importance of dialogue between Turkey and the EU.

The uneasy relations between Turkey and Greece date back to the creation of the modern Turkish republic out of the ruins of the Ottoman Empire.

Erdogan’s Islamic-rooted Justice and Development Party (AKP), which came to power in 2002, sought a more pragmatic relationship based on trade and tourism, and Greece became a key backer of the Turkish bid to join the EU.

“Erdogan’s visit can be seen as part of the long phase of rapprochement between the two countries that began in 1999,” Dimitrios Triantaphyllou, director of the Centre for International and European Studies at Kadir Has University in Istanbul, told AFP.

But he said while relations can be seen as “relatively robust”, none of a range of outstanding issues between the two sides has been resolved.

“Beyond the pragmatism, a wide divide exists between the two countries,” he said.

Athens is unhappy over Turkey’s upkeep of Byzantine heritage in Istanbul, the former Constantinople, including the Hagia Sophia, which is officially a museum but has seen an uptick in Muslim worship in the last few years.

Another festering sore is Cyprus, where the northern part of the island is still occupied by Turkish troops following the 1974 invasion in response to an Athens-inspired coup aimed at uniting it with Greece.

Much-touted peace talks this year to reunify the island ended without a breakthrough.

In a move seen by Turkish commentators as a gesture to Ankara ahead of Erdogan’s visit, nine suspected members of the Marxist Revolutionary People’s Liberation Party-Front (DHKP-C), branded a terrorist organisation by Turkey, were last week charged by a Greek prosecutor.