NICOSIA, July 28 (Reuters) - U.N. Secretary-General Antonio Guterres begins 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.

Two days before UN Secretary-General Antonio Guterres is due in Cyprus, Prime Minister Kyriakos Mitsotakis met Cypriot President Nikos Christodoulides in Athens on Saturday.

The European Union is stepping up efforts to join the resolution process on divided Cyprus, despite severely lacking neutrality, eroding the trust of...