What will happen to south Lebanon once UNIFIL leaves?

The United Nations Security Council on 28 August voted to renew the mandate of the UN Interim Force in Lebanon (UNIFIL)'s mission until 31 December 2026.

After that date, UNIFIL will start “an orderly and safe drawdown and withdrawal” over the course of 2027, concluding its 48-year mandate in southern Lebanon.

Established in 1978 through UN Security Council Resolutions 425 and 426, UNIFIL was tasked with overseeing the withdrawal of Israeli forces from southern Lebanon following the first invasion, restoring international peace, and helping Lebanon reassert authority in the area.

Its mandate was expanded in 2006 under Resolution 1701, following the 34-day war between Israel and Hezbollah, to ensure a full cessation of hostilities, assist the Lebanese Armed Forces (LAF) in disarming all armed groups south of the Litani River, and maintain a presence alongside the army as the only armed force in the region.

The decision to end UNIFIL’s mission comes at one of the most critical moments in Lebanon’s history, with the UN peacekeepers’ withdrawal expected to heighten instability.

Although a ceasefire signed in November last year between Israel and Lebanon ended the 2024 Israel-Hezbollah war, the Israeli army continues to occupy five strategic points in the south.

It also carries out frequent strikes against alleged Hezbollah sites, and at least 310 people have been killed since the ceasefire came into effect, according to data from the Ministry of Health.

From a security perspective, while UNIFIL’s presence in southern Lebanon has provided a key deterrent, it did not prevent Israel’s 2024 invasion. The UN peacekeepers have also been frequently targeted by Israeli attacks.

Their withdrawal is, therefore, expected to increase the risk of military clashes, reduce the LAF’s ability to control the border, and eliminate UNIFIL’s previous role as a channel for indirect negotiation and de-escalation, making it harder to defuse tensions along the border.

Chiara Ruffa, a professor in political science at Sciences Po in Paris, told The New Arab that the withdrawal of UNIFIL would likely leave a security vacuum in southern Lebanon, as its support for the LAF and its monitoring of violations would cease to exist.

This would create a “higher risk of escalation between Israel and Hezbollah and, potentially, Israeli reoccupation, starting from the five outposts they are already occupying, leading to a full-fledged invasion of at least parts of southern Lebanon at the first sign of insecurity”, she said.

In the short term, the end of UNIFIL’s mandate is expected to benefit Israel, according to Imad Salamey, professor of political science and international affairs at the Lebanese American University.

“Without international monitors, it [Israel] gains the upper military hand, with more freedom to act along the border without being constrained by oversight or mediation,” he told TNA.

UNIFIL also served as a mediator and a buffer force that helped contain disputes and prevent escalation, and Lebanon could become more vulnerable as the army loses a critical partner in managing security incidents. Hezbollah, meanwhile, would lose the diplomatic cover UNIFIL provided to help manage new crises, Salamey added.

Israel’s potential creation of a buffer zone after UNIFIL withdraws would align with its current military doctrine, prioritising force over diplomacy, political solutions, and multilateral institutions, according to Ruffa.

“Dismantling UNIFIL would place Israel in a favourable position, free of witnesses or monitoring of mechanism violations and with an army that is much more prepared and combat-ready,” she said.

“Given its existing occupation of five outposts in southern Lebanon, any sign of insecurity or LAF inability to control Hezbollah and maintain stability could prompt the IDF to establish a buffer zone or even reoccupy all of southern Lebanon, irrespective of Hezbollah’s potential disarmament.”

The planned end of UNIFIL’s mandate is, in fact, closely tied to Lebanon’s efforts to assert control over southern Lebanon and address Hezbollah’s arms.

With the UN peacekeepers’ withdrawal, responsibility for maintaining stability along the border would fall even more heavily on the Lebanese government, which has to face, externally, ongoing Israeli threats and, domestically, the issue of Hezbollah’s disarmament, which has the potential to create a political crisis.

Since taking office, Lebanon’s Prime Minister Nawaf Salam and the country’s new President Joseph Aoun have worked diplomatically to stop Israeli attacks, while also vowing to reinstate the state’s monopoly on arms and disarm all militias, including Hezbollah, which firmly rejects disarmament without Israel first withdrawing from Lebanon’s territory and halting attacks.

Lebanon’s government on Friday welcomed an army plan to disarm Hezbollah, despite the walkout of the five Shia ministers. However, no timeline was set, and officials cautioned that the army’s capabilities are limited. Hezbollah official Mahmoud Qmati called the decision "an opportunity to return to wisdom and reason, preventing the country from slipping into the unknown," Reuters reported.

Meanwhile, the US and Saudi Arabia are pressuring the Lebanese government to disarm the group, linking progress on this issue to potential financial aid for Lebanon's reconstruction and economic recovery.

But Hezbollah's disarmament remains a deeply divisive issue domestically, with significant political and sectarian opposition.

Retired LAF Brig. Gen. Andre Bou Maachar told TNA that Lebanon is caught in a vicious cycle: the army needs international support to build the capabilities required to disarm Hezbollah, but necessary aid is blocked until disarmament begins. At the same time, Israel continues military operations and violates Lebanese territory, complicating these efforts.

“Resolving the crisis requires a coordinated approach: unlocking international support, launching the army’s disarmament plan, and securing Israel’s withdrawal from Lebanon and compliance with international law,” he said.

The Lebanese army relies heavily on foreign aid to maintain operations, primarily from the US and other international partners. In March, the US State Department unfroze $95 million in aid to the LAF as an exception amid the Trump administration’s foreign-aid freeze.

Last week, it was reported that inaction on disarming Hezbollah could lead the US Congress to halt around $150 million in annual funding for the LAF. Hence, the army may face challenges in maintaining a full presence in southern Lebanon, particularly without UNIFIL’s support.

Military expert Riad Kahwaji told TNA that the LAF “has the ability to establish control if there is political will from the government, and if the army receives the financing, equipment, and armaments needed to remain modernised and efficient”.

He recalled that the LAF once controlled South Lebanon before 1975, but instability grew after the 1969 Cairo Agreement, which allowed the Palestine Liberation Organisation (PLO) to launch attacks on Israel from the south. The Lebanese Parliament annulled the agreement with the PLO in 1987.

Today, Kahwaji said, the Lebanese government seeks to restore that pre-1975 stability.

Maachar added that while the LAF remains legally responsible for defending Lebanese territory, establishing sovereignty, and implementing UN resolutions, the withdrawal of UNIFIL will significantly increase this burden.

“There will be a greater need for support, personnel, equipment, and dedicated forces to fill the gap,” he said. “What changes is the magnitude, the weight of the burden, but the LAF’s mission itself won’t change.”

With the situation along the Israel-Lebanon border remaining highly volatile, Salamey believes that the outlook is not promising, with hardline positions on both sides. The current status quo could persist for months, even years, without a breakthrough.

“In the absence of international monitoring, Israel may well operate unilaterally, striking at will and effectively creating a buffer reality without ever formally declaring one,” he said.

“Any long-term stability will depend on broader regional shifts, such as progress in Israeli-Palestinian negotiations, and a recalibration of Israeli–Iranian dynamics. Until then, the South will remain caught in a precarious balance."

Dario Sabaghi is a freelance journalist interested in human rights 

Follow him on Twitter: @DarioSabaghi