Blue Line (Lebanon)

The Blue Line is a border demarcation between Lebanon and Israel published by the United Nations on 7 June 2000 for the purposes of determining whether Israel had fully withdrawn from Lebanon.

At the same time, an extension, expressly "not to be called the Blue Line" corresponds to the nominal Lebanese–Syrian border between Lebanon and the Israeli-controlled Golan Heights.

On 11 March 1978 Palestine Liberation Organization (PLO) operatives, led by Dalal Mugrabi, carried out the Coastal Road massacre within Israel which resulted in the deaths of 37 Israelis, including 13 children. In response, Israeli forces invaded southern Lebanon from which the PLO operated regularly during the 1970s. Starting on the night of March 14–15 and culminating a few days later, Israel Defense Forces (IDF) troops occupied the entire southern part of the country except for the city of Tyre and its surrounding area. This operation is known in Israel as Operation Litani.

On 15 March 1978 the Lebanese government submitted a strong protest to the United Nations Security Council against the Israeli invasion, stating that it had no connection with the Palestinian operation. On 19 March 1978 the Council adopted Resolution 425, in which it called upon Israel to cease immediately its military action and withdraw its forces from all Lebanese territory. It also established the United Nations Interim Force in Lebanon (UNIFIL). The first UNIFIL troops arrived in the area on 23 March 1978.

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