The outposts were cover for “underground warehouses and munitions storage tunnels”, the US treasury claimed and had “impeded” Unifil inspections.

Peacekeepers’ attempts to inspect the positions were blocked by the group, who said the posts were on private property and off-limits.

“Under the cover of Green Without Borders outposts, Hezbollah members conduct weapons training at firing ranges, patrol the surrounding area and maintain containerised housing units 25m from the Blue Line,” the US treasury claimed.

At the time of the sanctions, the organisation claimed it was “not an arm for anyone”.

Zouher Nahli, its leader, who was also sanctioned, said: “We as an environmental association work for all the people and we are not politicised.”

In July, the UN secretary general wrote to the security council requesting the latest 12-month extension of Unifil’s mandate, but admitting its difficulties. 

He said both sides were still violating 1701. He also said there were at least five “unauthorised firing ranges outside state control” in the area “used on a number of occasions by gatherings of individuals in military-style attire with weapons”.

He said that despite repeated requests to the Lebanese government, “visits to these sites were not facilitated”.

Since hostilities escalated after Hamas’ Oct 7 attacks, peacekeepers had often been unable to patrol or fly helicopters, and were sheltering in bunkers, he said.

Analysts said peacekeepers have also faced growing hostility from the local Lebanon population, perhaps deliberately inflamed by Hezbollah which is deeply entrenched in southern Lebanon.

The hostility and the desire to avoid flashpoints and protect troops had made it more difficult to enforce the resolution.

The Lebanese government, which includes members of Hezbollah’s political wing, has also been accused of limiting the peacekeepers’ access, and keeping them out of sensitive areas.