Updated

U.N. Secretary-General Antonio Guterres sought Thursday to steer the rival sides in the Cyprus peace talks to agreement on a broad range of issues holding back a deal to reunify the ethnically divided Mediterranean island nation.

But with negotiations dragging late into the day, there were few signs of an impending breakthrough.

"I think we have done all we can in this negotiation," Greek Foreign Minister Nikos Kotzias told reporters after an evening round of talks. "We've saved this process from collapse three times, but these negotiations have to be based on the rights of individuals, states, peoples and international law."

Appearing for the second time at the peace talks in the Swiss resort of Crans-Montana, Guterres looked to break the logjam on the ninth day of discussions. He shuttled between participants to gauge where they stood on key issues such as future security arrangements for Cyprus, which has been divided for 43 years.

The goal is to get the Greek Cypriots and the Turkish Cypriots to agree on a framework. The details would be worked out in the following weeks before a final accord ending Cyprus' division is put to the island's Greek and Turkish communities for a vote.

"What's needed is calm and patience," said Greek Cypriot President Nicos Anastasiades. "I know the limits and boundaries by which I'm negotiating."

Turkish Cypriot leader Mustafa Akinci said it will be "long night" of negotiations. Guterres will host a working dinner for all participants and will leave early Friday to attend the G-20 summit in Hamburg, Germany.

Key to progress in the talks will be the input of Cyprus' so-called guarantors — Greece, Turkey and Britain.

Although many issues remain unresolved, the island's future security remains a primary stumbling block. The issue revolves around the more than 35,000 troops that Turkey has kept in the island's breakaway Turkish Cypriot north since 1974, when it invaded following a coup mounted by supporters of uniting Cyprus with Greece.

Greek Cypriots perceive the Turkish soldiers as a threat and want them to leave. The island's minority Turkish Cypriots want them to stay as their protectors.

Turkey's foreign minister said this week that a full troop withdrawal was out of the question. Greece also wants military intervention rights that Cyprus' 1960 constitution granted to the guarantors abolished. Turkey wants to retain some of those rights.

Anastasiades on Wednesday submitted a new set of proposals that included a key concession to Turkish Cypriots on taking turns holding the federal presidency in order to nudge the talks toward a deal.