A major archaeological project in Turkey that involves about 200 researchers has been shut down early, an apparent victim of international politics. The Austrian Archaeological Institute (AAI) in Vienna was notified last week by the Turkish Ministry of Culture and Tourism that its project at the ancient city of Ephesus near Selçuk, Turkey, would have to end immediately.

“This is a major shock,” says Sabine Ladstätter, AAI director and head of the excavation. A smaller excavation that AAI runs at Limyra, Turkey, was also ordered to shut down. The future of the projects remains in question.

The decision was reportedly made by Turkey’s Ministry of Foreign Affairs. No reason for the closure was given, but Austria’s chancellor, Christian Kern, had antagonized the Turkish government in August by saying the country was not fit to join the European Union. In a sign of the deteriorating relations, Ankara recalled its ambassador from Vienna on 22 August. The revocation of AAI’s two permits for fieldwork in Turkey appears to be the latest blow. “I regret this decision very much because it mixes politics and science, and is inconsistent with the partnership that we have fostered in Ephesus for many years,” Austrian science minister Reinhold Mitterlehner said in a statement to the media on Sunday. “With this step, the freedom of science is continuing to decline.”

Ephesus was founded by Greek colonists as a port on the Aegean Sea in the 1st century B.C.E., then expanded by the Romans. It is a United Nations Educational, Scientific and Cultural Organization World Heritage Site, a popular tourist attraction, and the site of research for more than 140 years. In 1869, a U.K. architect discovered the ruins of the Temple of Artemis, one of the seven wonders of the ancient world. Researchers with AAI have worked at Ephesus since 1895, interrupted by two world wars but not much else.

Ladstätter has carried out research at Ephesus for 23 years herself, and has led the excavations there since 2007. She had returned to Vienna early last week to get her daughter ready for the new school year when she heard that a letter had arrived from the Turkish government demanding that work at Ephesus be halted. Ladstätter immediately flew back to Turkey, where she had to shut down the operation, involving 100 employees, in 3 days. The team rushed to finish its drawings and photography, she says, cleaned up three excavations, and put boxes of supplies into storage. “We really worked day and night.” Her team also organized flights home for researchers visiting from Greece, Germany, and the United Kingdom.

The archaeologists had already wrapped up this season's excavations—of a Byzantine residential quarter and a Greek marketplace—but had planned to work on restoration projects at the site for another 2 months, repairing structures and protecting them from winter storms. “We are concerned about the potential for damage,” Ladstätter says. She does not know whether AAI will be allowed to apply for a permit to resume work next year. She is particularly concerned about 29 doctoral dissertations underway at Ephesus, many of which will require fieldwork next year.