Greece has warned Turkey of more European Union sanctions over its energy exploration in the Eastern Mediterranean.

The bloc has already imposed minor sanctions against Ankara over the matter and EU leaders are set to tackle the issue again at a summit in Brussels on September 24-25.

Speaking on Skai TV on Saturday, Greek government spokesman Stelios Petsas said that if Turkey does not take actual steps toward de-escalation, “things will become very difficult for [President Recep Tayyip] Erdogan at the European Council.”

Asked about a possible meeting between Prime Minister Kyriakos Mitsotakis and French President Emmanuel Macron, the spokesman said that no date has been confirmed.

He said that the two countries have sought to strengthen cooperation on all levels, including defense and security.