The Turkish president told reporters that "a guarantee without Turkey is not possible," as the Greek and Turkish Cypriot leaders attended a press conference following talks in Geneva.
Turkish President Recep Tayyip Erdogan said on Friday that Ankara would continue to base soldiers in the island of Cyprus as long as Greece does.
"We will stay in Cyprus forever. Turkey and Greece will keep their soldiers in Cyprus as discussed and agreed before. If we will talk about pulling soldiers out of the island then both sides will have to do that," he told reporters after Friday prayers in Istanbul.
Erdogan also said the Greek side was avoiding a solution to the Cyprus problem:
Erdogan's comments came after Greek Cypriot leader Nicos Anastasiades told a news conference on Friday that talks on reunifying Cyprus should produce a "radical" change in the island's security situation, which is currently guaranteed by Greece, Turkey and Britain.
Turkish Foreign Minister Mevlut Cavusoglu has described the presence of Turkish troops in the Turkish Republic of Northern Cyprus as a "force of stability," but the Greek Cypriot side wants them to be removed.
The current division of the island between the Turkish Cypriot north and Greek Cypriot south came about in 1974, when Turkey entered the north in response to a short-lived Greek-backed coup aimed at unifying Cyprus with Greece as well as longstanding communal violence and the marginalisation of the Turkish Cypriot community.
UN Envoy for Cyrpus, Espen Barth Eide, says that he is inspired by the negotiations so far. But he admits that both Greek and Turkish Cypriots question how a deal will be implemented, if it is agreed.
More specific talks are scheduled for Wednesday.