"Israel has once again accepted an Egyptian proposal for a complete cease-fire," a senior Israeli official said on the condition of anonymity. "This cease-fire is unlimited in time."
The deal was announced by Palestinian negotiators before it became official. It involves easing, but not lifting, an Israeli blockade to allow in construction materials and humanitarian effort into the Gaza Strip, with a monitoring mechanism to ensure the cement and concrete will go toward civilian projects, not rebuilding Hamas' underground tunnels.
"We're not interested in allowing Hamas to rebuild its military machine," the Israeli official said.
Hamas, meanwhile declared "victory" at the end of 50 days of bloody fighting that left 2,100 Palestinians dead and displaced at least a third of its 1.7 million residents.
"We declare the victory of the Palestinian resistance, the victory of Gaza," said Sami Abu Zuhri at a press conference in Gaza City. "We achieved some of our instantaneous demands out of this battle."
But many of the more sensitive demands, including the construction of a seaport and airstrip in Gaza, exchange of prisoners, and Israel's demand for the demilitarization of Gaza, will be taken up at negotiations in a month only if the cease-fire holds.
Even as the final touches on the deal were put in place Israel continued airstrikes, killing at least six people and leveling two high-rises.
Rocket fire also continued from Gaza, to the tune of more than 100 missiles, even shortly after the official cease-fire start at 7 p.m. An Israeli civilian was killed and two others were seriously injured when a mortar fell at a kibbutz in Eshkol, in southern Israel around 6:30 p.m.
In all, 64 Israeli soldiers and five civilians were killed in the conflict.
"We are all aware that this is an opportunity, not a certainty," said U.S. Secretary of State John Kerry. "We have been down this road before and we are all aware of the challenges ahead."