What is Israel's reported 'grey line' plan for southern Lebanon?

The Israeli military could establish a "grey line" in southern Lebanon that would effectively see it pull back closer to the border while maintaining its freedom of movement to strike.

According to a report by Israel’s public broadcaster, Kan, the security establishment is considering a significant reduction in forces deployed in southern Lebanon and a withdrawal from some forward positions, in exchange for establishing a new security zone extending three to four kilometres inside Lebanese territory from the border.

The plan, which has yet to be finalised and has not received approval from Israel’s political leadership, provides for the establishment of new military positions along the proposed line, where Israeli forces would be stationed. Tel Aviv claims this would be to protect northern communities in Israel from Hezbollah attacks and prevent the militant group from approaching the border again.

But talk of reducing the deployment does not amount to a full withdrawal. Keeping Israeli forces as far as four kilometres inside Lebanese territory would, in practice, mean maintaining a military presence across a strip of land containing towns, neighbourhoods and agricultural areas, while limiting residents’ ability to return to their homes and cultivate their land.

The absence of an official map of the proposed line has raised several key questions, including which towns and villages would fall within it.

Israel invaded southern Lebanon during fighting with Hezbollah at the start of October 2024 and retained five hilltops along the border. Since March this year, when all-out war resumed, Israeli forces have expanded their invasion of the region and now occupy swathes of southern Lebanon.

Earlier this year, the Israeli military established what it called the "yellow line", a security zone along the entire border spanning between eight and ten kilometres inside Lebanese territory. The zone includes dozens of southern towns and villages, many of which have been completely razed or heavily damaged as part of Israel’s scorched-earth policy.

Political analyst Karim Bitar said the terminology surrounding the various zones and lines risked obscuring what he described as a broader Israeli strategy.

"Expressions that are constantly used – buffer zone, security zone, yellow line, blue line, green line, now grey line – are quite problematic because they end up giving the impression that what is happening is merely a security issue, while we are facing a clearly expressed expansionist policy," Bitar said.

"What is striking is that the Israelis and their leading officials – I’m talking about Netanyahu and Katz, not only Ben-Gvir and Smotrich – are saying pretty much out loud what they are going to do," he added, in reference to Israel's premier, defence, national security and finance ministers respectively.

Ali al-Taher

According to Israeli reports, the proposed "grey line" is linked to the completion of operations in the Ali al-Taher ridge and the destruction of alleged Hezbollah infrastructure and tunnels that Israel says it has found beneath the hills.

The Israeli security establishment believes its control of the high ground has allowed it to reassess the scale of its troop deployment and move to a defensive line closer to the border.

Israel recently announced its capture of the highly strategic ridge, which overlooks the city of Nabatiyeh and large swathes of southern Lebanon and parts of northern Israel. Israel says one of Hezbollah’s largest command centres and military complexes lies beneath the ridge and plans to blow it up soon.

Defence Minister Israel Katz said the capture of the ridge had given Israel full control of the security zone, or "yellow line", along the border.

Hezbollah has neither confirmed nor denied Israel’s capture claims, nor has it responded to statements about blowing up the alleged underground fortress.

But shifting from forward positions to sites closer to the border, as proposed with the "grey line", does not resolve the fundamental issue. Even in its most reduced form, the plan would keep Israeli forces inside Lebanese territory, while a full withdrawal remains tied to unresolved security and political conditions, including a widescale deployment of the Lebanese army, the future of Hezbollah's arsenal and the outcome of US-sponsored negotiations.

Under a US-sponsored framework agreement signed in June between Beirut and Tel Aviv, Israel was supposed to start gradually handing over occupied towns and villages to the Lebanese army, which in turn would ensure that all Hezbollah infrastructure and weapons were dismantled and confiscated.

But implementation has made little progress as Israel refuses to withdraw and has escalated its deadly attacks on the south in recent nights, killing and injuring dozens. Israel says it will not pull out of Lebanon until Hezbollah fully disarms.

Hezbollah, for its part, has rejected the June deal and any disarmament efforts without an Israeli withdrawal.

Negotiation tactic?

The leak of the proposed "grey line" may be part of a negotiation process rather than an announcement of a final military plan. Israel could present a reduction in its occupying forces as a concession while effectively maintaining a security zone inside Lebanon, while demanding that Beirut take steps to extend state authority over the south.

Bitar compared the proposal to Israel’s use of territorial divisions during the Oslo Accords process in the occupied West Bank, arguing that such arrangements could allow Israel to delay difficult decisions while continuing to establish facts on the ground.

"What we are seeing in Lebanon is straight out of the Oslo playbook," he said. "At the time, Israel also divided the West Bank into areas A, B and C, and would often use this as a delaying tactic or a negotiation tactic whenever there was intense US pressure."

"They would promise to give more autonomy to one of the regions or to rein in the settlers, but ultimately they continued implementing their policy of establishing facts on the ground that rapidly became irreversible."

"I do not buy this idea that they will pull back closer to the border. Maybe right after the Israeli elections, if Israel needs a rebranding or wants to give the impression that it is negotiating in good faith, it might accept a few gestures of goodwill. But deep down, I think the strategy is to maintain an indefinite occupation of south Lebanon."

It also remains unclear whether areas that could be vacated by Israeli forces under the new "grey line" proposal would be handed directly to the Lebanese army or left devastated, under constant Israeli surveillance and within range of Israeli fire.

Negotiations between Lebanon and Israel have stalled, and a new date for talks this month, set to take place in Rome, is yet to be confirmed.

Bitar said the uncertainty surrounding the talks and the proposed security arrangements should make Lebanon wary of expecting an Israeli withdrawal.

"Many in Lebanon still succumb to wishful thinking by saying that these negotiations and this trilateral framework will end up leading to Israeli concessions," he said. "The time has come to wake up and smell the coffee and realise that what is happening in Lebanon is pretty much what happened 30 years ago with Oslo, when the peace process became a mere process."

"We are witnessing a similar situation in Lebanon, where all the delicate issues are being indefinitely postponed and we are talking of pilot zones, and even in these zones Israel is not showing good faith."

"The Lebanese army is facing an impossible situation, so there are few reasons to be optimistic and to believe these latest Israeli statements that they will pull back closer to the border."

Israel's offensive on Lebanon has killed more than 8,900 people, including 253 children, and injured more than 30,600, since it began in October 2023.