SHEIK EJLEEN, Gaza Strip — An unmarked dirt lot about the size of a football field, on a cliff above the crashing waves of the Mediterranean, could be a crucial element in ending the monthlong battle between Israel and Palestinian militants in the Gaza Strip.

It was here that a European contractor began building a commercial seaport back in July 2000, only to have its work destroyed by Israeli tanks and bombs within three months. Now, Palestinian leaders trying to negotiate terms in Cairo for a durable truce have made the revival of the seaport project a prime demand.

The port has become the embodiment of Palestinian aspirations to break the siege of Gaza, at once a symbol of independence and a potential economic engine that would reduce the territory’s reliance on increasingly hostile neighbors. First promised by the Oslo Accords in 1993, the seaport — or at least an interim proposal for a floating pier under international supervision — has won some backing from Europe, Egypt and the United Nations, albeit with caveats to address Israeli security concerns.

Gazans “view this as a steppingstone toward exercising some greater sovereignty over their own borders,” said Nathan Thrall, a senior analyst for the International Crisis Group, a nonprofit research group. “It’s enormously important practically and symbolically. It is establishing that there are these two powers that are squeezing us from both ends, and we are now going to change that situation and create a new opening for Gaza.”