Lebanon and Israel are closer than ever to signing a deal demarcating their maritime border, opening the door to new oil and gas exploration, after years of U.S.-brokered negotiations.

While limited in scope, the agreement is set to ease security and economic concerns in both countries, whose shared history is rife with hostility. The deal will only resolve a territorial dispute in the eastern tip of the Mediterranean sea and does not touch on their land borders, which are yet to be settled.

Here are some details of the U.S. proposal that is being discussed on Thursday by Israel’s top ministers :

WHAT WILL THE MARITIME BORDER LOOK LIKE? 

The border begins around a rocky cliff overlooking the Mediterranean where a U.N. peacekeeping force is headquartered.

The U.S.-proposal, according to Israeli officials, splits the sea border into two sections. The first five km (3.1 miles)from shore will be set along a line that Israel set as its border years ago and has already marked with a row of buoys.

Beyond that, the border will follow a line initially proposed by the Lebanese that is referred to as Line 23. This will demarcate each country’s exclusive economic zone (EEZ).

WHAT ABOUT OIL AND GAS EXPLORATION?

Israel has discovered huge deposits of natural gas in its EEZ that is both used domestically and exported.

Lebanon has lagged behind. While licences there were issued for two blocks, no production has happened and other blocks have yet to receive bids. A sizeable discovery could help ease Lebanon’s financial crisis, which has left the state unable to import fuel for its power plants.

There is one gas field in a southern Lebanese exploration block, Qana, that extends across Line 23 into Israeli waters. It is estimated to be small and has yet to be explored. Should commercial quantities be found, Israel’s prime minister said the deal allows Israel to get a share of royalties from the field.

Israeli officials have already met TotalEnergies to discuss a mechanism. Lebanon’s top negotiator Elias Bou Saab said Lebanon had retained its rights with Qana and that Beirut would not pay “one cent” from its part of the field to Israel.

A second field Karish, which is being developed under an Israeli licence farther south and due to come online soon, has been threatened by the heavily-armed Lebanese group Hezbollah. Karish is located below Line 23 and will remain under Israeli control, Israel says.

Bou Saab said Lebanon has retained “all” of its maritime blocs.

COULD THIS LEAD TO FURTHER DIPLOMACY?

Settling the land border dispute between Lebanon and Israel is much more complicated and lacks the urgency of the energy component. Any resolution there would likely depend on a broader peace deal that is not realistic anytime soon.

Israeli leaders have said only that the maritime deal would help regional stability. Lebanon’s president said that a deal would not signify a “partnership” with Israel.

“We are avoiding a sure-fire war in the region,” Lebanon’s caretaker PM Najib Mikati said on Thursday.

The first grain ship to leave a Ukrainian port under a deal brokered last month will not arrive in Lebanon on Sunday as planned, the Ukrainian embassy in Lebanon said.

The Razoni left Odesa on the Black Sea early last Monday carrying 26,527 tonnes of corn and was set to dock on Sunday in the northern Lebanese port city of Tripoli, according to Ukrainian officials and Lebanese port authorities.

But the Ukrainian embassy in Lebanon told Reuters on Sunday the ship was “having a delay” and “not arriving today,” with no details on a new arrival date or the cause of the postponement.

Shipping data on MarineTraffic.com showed the Razoni off the Turkish coast on Sunday morning.

The vessel’s bill of lading, a copy of which was seen by Reuters on Sunday, had the expected arrival date as Tuesday and listed the cargo destination as “to order,” which typically means that a ship’s cargo can be transferred from one owner to the next.

Lebanon’s transport, agriculture and economy ministers all told Reuters last week they did not know who was purchasing the grain aboard the Razoni.

The shipment was made possible after Turkey and the United Nations brokered a grain and fertilizer export agreement between Moscow and Kyiv last month – a rare diplomatic breakthrough in a drawn-out war of attrition.

The U.N. had warned that the halt in grain shipments from Ukraine through the Russian-dominated Black Sea could prompt outbreaks of famine around the world.

The Joint Coordination Center (JCC), which will oversee the export of Ukrainian grain, said the ship would be used as a trial run, with information from Razoni’s crew used to fine-tune procedures for the next shipments.

Ukraine asked Lebanon’s top prosecutor on Wednesday to reopen a probe into a ship Kyiv says was carrying stolen grain that remains docked in Lebanon pending a seizure order.

Ukraine says the Syrian-flagged ship, in the northern Lebanese port of Tripoli, is carrying some 10,000 tonnes of flour and barley plundered by Russia following its February invasion.

Ukraine’s ambassador to Lebanon, Ihor Ostash, told a news conference at the embassy near Beirut that the request to investigate further was based on new evidence gathered by a Ukrainian judge and handed over to Lebanon on Monday.

The Lebanese prosecutor, Ghassan Oueidat, lifted a first seizure order on the Laodicea ship he had issued last week after finding no criminal offence committed. But it remains unable to sail until at least Thursday due to another order from a judge in Tripoli.

Moscow has previously denied stealing grain. Russia’s Embassy in Lebanon said it had no information on the cargo.

An official from the company that owns the cargo has also denied it was stolen and said the ship would sail to nearby Syria should it be allowed to leave.

Ukrainian authorities say the Laodicea travelled to a port in Russian-occupied Crimea closed to international shipping and that it took on cargo there before sailing to Lebanon.

Ostash added that a ship carrying 26,000 tons of corn, the first carrying Ukrainian grain to leave its Black Sea ports with cargo for international markets since Russia’s invasion, would arrive in Lebanon within four to five days.

He said Ukraine remained commited to supporting Lebanon with grain shipments as Lebanon deals with shortages of basic goods including wheat amid a three-year financial collapse.