PERCHED atop an island on the Marmara Sea, off the coast of Istanbul, and accessible only on foot or by horse buggy, the Halki seminary hardly seems like a suitable stage for political drama. Creaky wooden desks face blank chalkboards inside empty classrooms. Chanting from a small chapel next to the school echoes past the tombstones of former patriarchs and the surrounding trees. A vegetable garden overlooks a grey sweep of sea and the dense Istanbul skyline beyond. Flocks of chickens and ducks, a goat, a couple of sheep and seven peacocks wander around a small stable. Seagulls cry overhead.

But it is here, within the walls of the school, that a diplomatic dispute has been brewing for nearly five decades. Founded under Ottoman rule in 1844 near the site of a much older Byzantine monastery, Halki used to be one of the most important theological centres of Greek Orthodoxy. A dozen of its graduates went on to become heads of the Ecumenical Patriarchate of Constantinople, housed in an Istanbul neighbourhood an hour away by ferry and regarded as the heart of the Orthodox world. Months ahead of an army coup in 1971, Turkey banned private higher education, forcing the seminary to close. Despite pressure from America, the European Union and Greece, successive Turkish governments have refused to reopen it. A few priests, a handful of cleaners and gardeners, plus a cook and an ironing lady are the building’s sole occupants. Halki remains a school without students.

Hopes of a breakthrough have come and gone. The latest arrived on February 6th, when Alexis Tsipras, accompanied by the current Ecumenical Patriarch, Bartholomew, became the first sitting Greek prime minister in history to visit the seminary. An aide to the Turkish president, Recep Tayyip Erdogan, was also on hand. (Mr Erdogan’s government has engaged with Turkey’s Christian minority more readily than its predecessors.) The mood was relatively upbeat. “I hope my next visit here will be with President Erdogan, and that together we will open the doors of this school,” said Mr Tsipras, to loud applause. A day earlier, following a meeting between the two leaders, Mr Erdogan suggested there were few legal obstacles to reopening Halki.

There are plenty of political ones, however. Mr Erdogan and Mr Tsipras enjoy some personal chemistry, but Turkey’s relations with Greece remain marred by disputes over maritime borders, gas reserves in the Aegean, the reunification of Cyprus and the fate of eight Turkish troops who escaped to Greece after an abortive coup in 2016. (Turkey wants them extradited.) At its core, the fate of the seminary is a matter of Turkey’s commitments to its own religious minorities, and not a bilateral issue. Mr Erdogan has had no qualms about making it into one. During his press conference with Mr Tsipras, the Turkish strongman linked the opening of the seminary to the rights of Greek Muslims in western Thrace. “You come and solve Thrace, and we will solve this,” he said.

Greece is unlikely to engage in such barter, says Dimitrios Triantaphyllou, a Greek academic working in Turkey. Yet there is some chance that Mr Erdogan will make the first move. The Turkish leader, whose image in Western capitals has taken a battering over the past decade, appears increasingly eager to placate foreign critics, especially with the Turkish economy now facing recession. Halki would be an easy way of doing that. “Opening it would send a good message,” Mr Triantaphyllou says. “Turkey has nothing to lose.”

For the old seminary, time may be running out. Hostage to historical tensions and other disputes, the Greek population of Turkey has dwindled from over 100,000 in the 1950s to under 2,000 today. The patriarchate, whose officials, including the patriarch, are required by law to be Turkish citizens, is struggling to find clerics to tend to its churches. As a stopgap measure, Turkey has granted citizenship to several priests brought over from Greece. Mr Erdogan can do more. Turkey’s president has a knack for summoning (and burnishing) the legacy of the Ottoman Empire, including its laudable record on religious freedoms. He might want to do so again, and reopen Halki.