Turkey believes it futile to discuss a bizonal bicommunal federation as the template for a Cyprus settlement, and will make this clear at the upcoming conference in Geneva, the country’s foreign minister said Thursday.

“There is no sense to negotiate the impossible again, it is a waste of time,” Mevlut Cavusoglu told Turkish channel NTV.

“This waste of time works to the benefit of the Greek Cypriot side, which enjoys recognition [as a state] and membership of the European Union.”

Speaking ahead of talks with his Greek counterpart, Cavusoglu said that “on our way to Crans Montana [in 2017] we told our interlocutors that we are going to discuss a federation for the last time.”

The chief Turkish diplomat added that they will be making their position clear at the five-way informal summit on Cyprus set to take place from April 27 to 29 in Geneva.

Cavusoglu reiterated that, for the Turkish side, the conversation has shifted to establishing two separate states on the island.

“The two sovereign states can cooperate in any way. We need to speak about a cooperation between two sovereign states, rather than press on for something that would never happen.”

Later in the day Cavusoglu and Greek Foreign Minister Nikos Dendias clashed openly at a joint news conference in Ankara that began with hopes of improved relations but quickly descended into acrimonious accusations from both sides.

Seeking to ease months of tensions over territorial disputes in the eastern Mediterranean, Dendias met Turkish President Tayyip Erdogan and Cavusoglu in the first visit by either side since their navies came close to fighting last year.

However an initially cordial atmosphere at a media appearance following the meetings turned sour as Dendias said violations of Greek sovereignty would be met by sanctions and Cavusoglu rejected his comments as “unacceptable.”

“You come out here, and try to accuse Turkey, to give a message to your country. It is not possible for me to accept this,” Cavusoglu said in response to the remarks.

The two countries are allies in Nato but at odds over many issues, such as competing claims over the extent of their continental shelves in the Mediterranean, air space, energy resources, ethnically split Cyprus, and the status of some islands in the Aegean.

Tensions flared last summer when Turkey sent a drilling ship to contested Mediterranean waters, but have eased slightly after Ankara withdrew the vessel and the countries resumed bilateral talks over their disputes following a five-year hiatus.

Having begun by offering Greek support to Turkey’s bid to join the European Union and a new agenda to reset relations, Dendias accused Turkey of repeatedly sending aircraft over its territory.

“Greece’s position is clear. Turkey has violated international law and maritime law in the Aegean and eastern Mediterranean,” Dendias said.

Cavusoglu rejected the charge, saying Turkey had not infringed on Greek sovereignty in its search and drilling work and accusing Athens of pushing back migrants in the Aegean.

“When we get into mutual accusations, we have a lot to tell each other. If you want to continue these arguments, tensions, you can (and) we will do so as well,” he added.

However both sides said they wanted to continue to try to resolve their differences through dialogue.