Israel and Lebanon resumed U.S.-mediated talks on Nov. 11 over their disputed Mediterranean Sea border, which has held up hydrocarbon exploration in the potentially gas-rich area, a source and Lebanon’s state news agency said.

The longtime foes held three rounds of talks in October hosted by the United Nations at a peacekeeper base in southern Lebanon that the U.N. and the United States had described as “productive.”

But sources had said gaps between the sides remain large after they each presented contrasting maps outlining proposed borders that actually increased the size of the disputed area.

Israel already pumps gas from huge offshore fields but Lebanon, which has yet to find commercial gas reserves in its own waters, is desperate for cash from foreign donors as it faces the worst economic crisis since its 1975-1990 civil war.

The meetings are the culmination of three years of diplomacy by Washington and follow a series of deals under which three Arab nations—the United Arab Emirates, Bahrain and Sudan— agreed to establish full relations with Israel.

Lebanon has said its talks are strictly limited to their disputed boundary.

Offshore