As long as they lease the aircraft there are no problems and the US sanctions seem not to apply for leased aircraft (they've even leased a B737-400 for a while). However, since the demise of Transaer and the leased B737-400 not flying for LN anymore I haven't seen them at AMS and every Sunday they always cancel the flight.
BTW Air France is very late in restoring flights to Libya. All other major European airlines already have flights to Tripoli.
BTW the Libyan Airlines flight to CDG is still not in the CRS