DUBAI, United Arab Emirates (AP) — An initial agreement between the United States and Iran to extend their shaky ceasefire inched toward a formal signing despite questions Monday over the fate of Tehran’s nuclear program and an offensive by Israel in Lebanon that could prolong the fighting and scuttle the deal.The agreement signed electronically Sunday is meant to provide a meaningful truce in a monthslong war that has killed thousands across the Middle East, including the top leaders of Iran’s theocracy, and raised the prices of fuel, food and other basic goods far beyond the region. But logistical and military challenges underscored the fragile nature of the deal, which was set for a ceremonial signing Friday in Geneva.At the core of the pact is a planned reopening of the Strait of Hormuz, a crucial waterway whose blockage has choked the supply of the world’s oil and natural gas. Yet even a full reopening would not immediately alleviate the global energy crisis its closure created.

Another potential obstacle concerns Israel, which joined the U.S. in launching the war on Feb. 28, but it is not party to the deal. The Israeli military launched airstrikes Sunday in southern Lebanon, where it is fighting the Iranian-backed Hezbollah militant group, and the Israeli defense minister said Monday that the country would not withdraw from land seized in Lebanon, where Israel is fighting the Iranian-backed Hezbollah militant group.