"...In a Beirut 'meeting' with Gemayel, Chamoun, Georges Adwan & Abu Arz, Sharon set forth the battle plans..."

Haaretz, here

"....One of the Mossad's most important missions from the day of its inception was Israel's "special relations" with countries that did not recognize it and with minorities like the Christians in Lebanon and the Kurds in Iraq. This was the declared policy of the governments of Israel: Israel will be prepared to come to the aid of any threatened minority that is fighting for its existence - but it will not fight in its stead..... Iran, under the shah, took an interest in Lebanon and flew in arms to defend the Christians.....
The Mossad's relations with the Christians enabled the senior IDF brass, including the commanders of the forces in the field, to reconnoiter as far as Beirut, and to receive the necessary intelligence.....
In January 1982, at a meeting in Beirut with top Christian leaders - Pierre Gemayel, Camille Chamoun, Georges Adwan and Etienne Saqr (Abu Arz) - Sharon set forth the battle plans......"