beirut tahrir al-sham alliance jihadist factions syria saturday decry turkey-backed syrian rebel factions plan operation northwestern idlib province dominate say would picnic lions jihad martyrdom wait pounce add statement post social media site early saturday turkish president tayyip erdogan say syrian rebel fighters prepare launch serious operation idlib back turkish force inside turkey border operation come agreement last month turkey russia iran set de-escalation zone northwest syria idlib locate reduce warfare erdogan say russia back syrian government rebel group would support operation rebel take part say russia role areas control syrian government tahrir al-sham statement describe rebel group involve traitors accuse work russia syrian government without mention turkey syrian jihadist alliance decry rebel group plan incursion statement