Israel and Hamas have been holding indirect talks for more than a year aimed at ending the war in Gaza and returning scores of militant-held hostages in exchange for Palestinians imprisoned by Israel. But despite intensive mediation by the United States, Qatar and Egypt, the talks have repeatedly stalled over several key issues, including the details of the exchange, whether the ceasefire would be permanent and the withdrawal of Israeli forces. As each side has accused the other of backtracking, the war has ground on.