Israel has signed an initial agreement with TotalEnergies SE and Eni SpA that allows the energy companies to start exploring for natural gas within the framework of a landmark maritime border deal with Lebanon.

Lebanese and Israeli leaders last month finalized a U.S.-brokered maritime demarcation deal, bringing a measure of accommodation between the enemy states.

A focus of the deal was settling a dispute over a potential gas field in Lebanon’s offshore Block 9 that extends into Israeli waters. TotalEnergies is the operator of Block 9 with a 60% interest. Eni holds 40%.

“The Block 9 partners will initiate the exploration of an already identified prospect which might extend both in Block 9 and into Israel waters south of the recently established maritime borderline,” TotalEnergies said on Nov. 15.

Lior Schillat, director-general of Israel’s energy ministry, said the agreement would “allow the development of a gas reservoir that crosses the border between enemy states, an unusual event in the global energy market.”

A final, more detailed arrangement will be signed if commercial quantities are discovered, the energy ministry said.