Talks aimed at reunifying ethnically divided Cyprus were restarted today with rival leaders hoping to claw back diminished trust and lost momentum after a two-month halt. <br/><br/>But the United Nations-mediated negotiations still face difficult challenges, with the island's Greek Cypriot president accusing the breakaway Turkish Cypriot leader of backpedaling on key issues at Turkey's prompting after many months of solid progress.<br/><br/>The minority Turkish Cypriots, meanwhile, say Greek Cypriots pay lip service to their core demand of equal partnership in the running of an envisioned federation – especially on holding the federal presidency alternately.<br/><br/>Cyprus was split in 1974 when Turkey invaded following a coup mounted by supporters of union with Greece. A breakaway Turkish Cypriot state in the island's north is recognized only by Turkey which keeps more than 35,000 troops there.