NICOSIA, July 28 (Reuters) - U.N. Secretary-General Antonio Guterres launched a fresh effort on Tuesday to coax Cyprus' rival sides back into peace talks after nearly a decade of deadlock.

His first visit to the island as U.N. chief comes amid signs the sides may be ready to negotiate again, but they remain divided over the ground rules for talks. Failure would prolong a dispute that strains ties between NATO allies Greece and Turkey and weighs on Ankara's relations with the European Union.

Guterres, whose term expires at the end of 2026, met Greek Cypriot leader Nikos Christodoulides and Turkish Cypriot leader Tufan Erhurman separately on Tuesday. The three will hold joint talks on Wednesday in the U.N.-controlled buffer zone that divides the island.

Cypriot media have reported that the United Nations has compiled a set of ideas aimed at bridging differences between the sides, though U.N. officials have denied a completed plan exists.

Guterres said he wanted to show his strong commitment to a solution in Cyprus. "It depends obviously on the Cypriots themselves ... I will do everything I can to support the Greek Cypriots and Turkish Cypriots in this very important moment," he said after meeting the Greek Cypriot leader.

DIFFERING POSITIONS

Christodoulides wants to resume negotiations from where talks collapsed in 2017, under a U.N.-backed model of a bizonal, bicommunal federation.

Erhurman, elected Turkish Cypriot leader last year, campaigned on exploring a federal settlement, a break from his predecessor's demand for a two-state solution. However, he says he will not enter another open-ended process without prior agreement on political equality and the rules governing negotiations.

Cyprus was split after a Turkish invasion in 1974 in response to a brief coup engineered by the military then ruling Greece. Britain, Greece and Turkey are "guarantor powers" with intervention rights under a treaty giving the former colony independence in 1960.

UN PEACEKEEPERS

A power-sharing administration of Greek and Turkish Cypriots crumbled in 1963, and a United Nations peacekeeping force, now one of the oldest peacekeeping operations in the world, was dispatched less than a year later. It monitors a 180 km (112miles) ceasefire line splitting the two sides.

The south is run by an internationally recognised Greek Cypriot government which represents the whole island in the European Union, whose rotating presidency it just held in early 2026. The north is a breakaway Turkish Cypriot state recognised only by Ankara.

One of the reasons past talks collapsed is strong disagreement on the role Turkey would play in any post-settlement deal. Greek Cypriots are against Ankara having any hands-on involvement, while Turkish Cypriots say it isessential.

Turkey publicly advocates two separate states in Cyprus, a position rejected by Greek Cypriots and Greece.

(Reporting by Yiannis Kourtoglou and Marinos Meletiou, Writing by Michele Kambas; Editing by Michael Perry and David Holmes)