Overview
On August 28, 2025, the United Nations Security Council (UNSC) adopted Resolution 2790 (2025), renewing United Nations Interim Force in Lebanon's (UNIFIL) mandate for a final time through December 31, 2026, and directing a drawdown and withdrawal over the following year. The resolution breaks with the mission's customary annual renewals and sets a clear exit timeline. The move came amid sustained US-Israeli pressure to terminate the mission, with France brokering the compromise timeline. In practice, this means a 16-month "last extension," then a year to pack up—effectively ending nearly five decades of UN peacekeeping presence in southern Lebanon by the end of 2027.
UNIFIL's Mixed Record: Tactical Success, Strategic Limitations
UNIFIL currently deploys approximately 10,500 peacekeepers from 47 countries in southern Lebanon, plus a Maritime Task Force (MTF). After nearly half a century of operations, the mission presents a complex legacy of both achievements and limitations. While UNIFIL has successfully maintained relative stability along the “Blue Line,” the Israel-Lebanon border, for extended periods and prevented numerous local incidents from escalating, it has struggled to fulfill its broader mandate of ensuring southern Lebanon remains free from unauthorized armed personnel and weapons.
The mission's defenders correctly point to its "liaison, de-escalation, and presence" functions—patrols, tripartite meetings, and hotline diplomacy along the Blue Line. Indeed, these activities have prevented countless minor incidents from spiraling into larger conflicts. On the other hand, critics argue that UNIFIL's passive monitoring approach has allowed Hizballah to build significant military infrastructure in violation of UN resolutions, specifically UNSC Resolution 1701. Israel, in particular, has long criticized UNIFIL as ineffective against Hizballah entrenchment, a view that has been partially vindicated by the group’s continuous clashes with Israel and Lebanese security forces. However, the mission did provide certain benefits, including international legitimacy for Israeli defensive actions and a buffer against unintended escalation.
The establishment of the US-led International Monitoring and Implementation Mechanism (IMIM) following the November 26, 2024, ceasefire reflects both UNIFIL's limitations and the international community's recognition that more robust monitoring mechanisms may be needed for complex security arrangements.
Lebanon's Changing Security Landscape
The Security Council's resolution expects the Lebanese Armed Forces (LAF) to assume control as UNIFIL withdraws—an expectation that faces significant challenges but also new opportunities. The LAF has historically operated under severe financial constraints and avoided direct confrontation with Hizballah, reflecting Lebanon's complex sectarian balance and the group's political influence.
However, recent developments have created potentially more favorable conditions for LAF expansion in the south. Hizballah has been significantly weakened by its conflict with Israel, which eliminated key commanders and demonstrated the vulnerability of its tunnel networks and weapons storage facilities. The group's financial resources have also been constrained by both the conflict’s costs and international sanctions. Iran's capacity to resupply and rebuild Hizballah has also been constrained by its own economic challenges and regional setbacks, creating a potentially unique window for Lebanese state institutions to assert greater control. While UNIFIL's departure removes an international witness to Hizballah's activities, the organization may lack the resources necessary to immediately rebuild its previous military presence in southern Lebanon.
The election of President Joseph Aoun and the appointment of Prime Minister Nawaf Salam represent a more assertive Lebanese leadership potentially willing to challenge non-state actors. European and Gulf pledges of support, while historically inconsistent, may prove more effective in this changed context. The key question remains whether international funding can be sustained long enough to build credible LAF capabilities, and whether Lebanon's new leadership has the political will to assert state authority throughout the country.
Key Concerns in a Pre- and Post-UNIFIL Security Landscape
UNIFIL's role in managing Blue Line disputes through tripartite talks has been both a strength and a weakness. While the mission has successfully frozen contentious issues like Ghajar and various border points from escalating into larger conflicts, it has failed to resolve these disputes definitively. The transition to UN Special Coordinator on Lebanon (UNSCOL) shuttle diplomacy and ad hoc third-party involvement will test whether direct bilateral engagement can succeed where multilateral peacekeeping has struggled. The reduced tensions following Hizballah's weakening may create new opportunities for progress on long-standing border issues.
UNIFIL's Maritime Task Force has provided domain awareness and liaison functions since 2006, with mixed results in preventing weapons smuggling. While the MTF has not eliminated maritime infiltration, it has raised the costs and complexity of such operations. The question now is whether Lebanon can develop independent maritime security capabilities or whether alternative international arrangements will be necessary.
European naval capacity, while declining, may be more effectively deployed in a focused maritime mission than as part of a broader peacekeeping mandate. The key will be ensuring any replacement mechanism has clearer rules of engagement and enforcement authority.
UNIFIL's civil-military cooperation projects have genuinely benefited local communities through medical outreach, infrastructure projects, and employment. The mission's departure will create economic disruption for local suppliers and staff, though this must be weighed against the broader security implications.
Regionally, Iran's weakened position limits its ability to immediately exploit UNIFIL's departure. Gulf states may see an opportunity to support LAF development as a counter to Iranian influence, while the new Lebanese leadership may be more receptive to such assistance than previous governments.
Three Scenarios for Transition
Looking ahead in the near term, there are three plausible scenarios that may be considered. First is a managed transition: A strengthened LAF, supported by sustained international funding and emboldened by Hizballah's weakness, gradually assumes security responsibilities. The new Lebanese leadership provides political backing for state assertion in the south. This scenario, while still challenging, is more plausible given current dynamics than it would have been before Hizballah's recent setbacks.
More plausible is an uneven handover: UNIFIL withdraws while LAF presence remains inconsistent across different areas. Hizballah maintains influence in some zones but lacks the resources to fully restore its previous military presence. Israel responds with increased surveillance and occasional precision strikes, but large-scale conflict is avoided due to Hizballah's diminished capabilities. This outcome is perhaps the most likely due to limited capacity on both sides.
There is also a risk of a security vacuum: LAF fails to establish meaningful presence, and Hizballah proves more resilient than expected in rebuilding capabilities. However, even in this scenario, the group's weakened state makes immediate major escalation less probable than in previous periods.
Timing and Opportunity
The UNSC’s decision to end UNIFIL comes at a potentially opportune moment when regional power dynamics have shifted significantly. Hizballah's weakening, Iran's constrained influence, and Lebanon's new leadership create conditions that may be more favorable for a successful transition than at any point in recent decades. UNIFIL's legacy will be debated, but a balanced assessment recognizes both its role in maintaining relative stability for extended periods and its failure to address underlying political and security challenges. The mission succeeded in its immediate mandate of reducing border tensions but struggled with the broader goal of ensuring Lebanese state authority throughout the country.
The critical question now is whether the international community and Lebanese leadership can capitalize on current conditions to build sustainable security arrangements. Success will depend on sustained international support, Lebanese political will, and the continued weakness of spoiler groups. While challenges remain significant, the confluence of factors creates the best opportunity in years for meaningful progress toward Lebanese state sovereignty in the south.
Post-UNIFIL Lebanese stability will be of serious concern for the country’s Middle Eastern neighbors, including Israel, Syria, and Gulf Arab states. Stabilizing Lebanon’s south and de-legitimizing Hizballah as a political and security force is an outcome everyone wants, whether to limit attacks into Israel, curb the flow of violence and destabilizing armed group activity, like arms transfers into Syria, or prevent Iran from reconstituting an arm of its diminished proxy network. While not currently the largest contributor to significant instability in the Middle East, Lebanon’s stabilization—or backslide into a power vacuum—will impact the region’s efforts to resolve overlapping crises.
