The United Kingdom will supply a fleet of vehicles "at no cost" to the Lebanese Armed Forces (LAF), the Defence Secretary said in a statement on Tuesday.
Ben Wallace said the decision was taken "in recognition" of the "strong relationship" between the two countries in "tackling the shared terrorist threat".
The Lebanese Armed Forces had requested the UK’s assistance in providing "suitable equipment" to give them the capability to fully patrol the border with Syria.
Mr Wallace said in the statement: "The UK has agreed to supply 100 surplus Army Revised Weapon Mounted Installation Kit Plus (RWMIK+) vehicles in response to a request from the Lebanese Commander in Chief."
He added that the RWMIK+ will "greatly enhance" the Lebanese Armed Forces' ability to "mount long-distance patrols" in mountainous terrain.
The aim is for the Land Border Regiments (LBRs) to use the vehicles to counter the threat of smugglers and extremists trying to cross the border into Lebanon.
Beirut is expected to start receiving the RWMIK+ this month.
The 100 RWMIK+ vehicles, valued at just over £1.5m in total, are "surplus to the needs of the British Army", Mr Wallace said in the statement.
Costs of collating and transporting the vehicles will be paid for by the Conflict, Stability and Security Fund.
The training in the operation of the vehicles will be borne by the Defence Acquisition Fund (South), the statement added.
Cover image: A library picture of a member of the British Army in a RWMIK+ Landrover in 2018 (Picture: MOD).