UN Secretary-General Antonio Guterres has written to UN Security Council members stressing the need ​for a continued uniform UN presence in Lebanon after the mandate of the UN Interim ‌Force in Lebanon (UNIFIL) expires at the year-end.

Guterres outlined three options to replace the 7,500-strong UNIFIL in a letter to the 15 members of the Security Council dated Monday and seen by Reuters.

They ranged from a light presence with limited capabilities to ​a more robust force with broader monitoring and de-escalation capabilities, and from around 1,980 to ​5,525 uniformed personnel.

The letter included the following details:

Guterres noted the situation in Lebanon had deteriorated ⁠dramatically since March and that under all proposed options, a uniformed UN presence would be necessary to ​support a strengthened UN political mission seeking a long-term solution to the conflict.

Option 1 foresees an unarmed military ​observer presence of 350 personnel, combined with an armed presence for force protection, including four infantry battalions of 750 troops each and a force reserve of 700.

Such a force would have the capacity to most credibly observe developments along the ​length of the Blue Line and up to the Litani River, Guterres wrote.

Option 2 envisages an unarmed ​military observer presence of 285 personnel, combined with an armed presence for force protection, including two infantry battalions of 750 ‌troops each ⁠and a force reserve of 450.

This force would focus on the area between the Litani River and the Blue Line and have the capacity to directly monitor some of the Blue Line through its physical presence, including from static observation posts and through patrols.

Option 3 would involve an unarmed military observer presence of ​215 personnel, combined with ​two light infantry battalions ⁠of 450 armed troops each and a quick reaction force of 350 armed troops for force protection.

It would monitor developments along the Blue Line and up to ​several km north, including from static positions at critical locations and through ​mobile observations.

However, the ⁠entirety of the Blue Line could not be continuously monitored without the necessary technological support, and there would be no capacity for the force to place itself between the Lebanese and Israeli forces to help de-escalate tensions.

The ⁠force ​would also have only a limited ability to provide information on ​ceasefire violations.

Guterres said any future uniformed presence would require air assets for medical evacuations, as well as de-mining and engineering capacities.

Radar, helicopters, ​drones and satellite imagery would also enhance the mission’s monitoring capacity.