. The boundary which later became the border between Israel and Lebanon was first created following the
First World War and the establishment of the British mandate of Palestine and the French mandate of Lebanon. Following the establishment of the State of Israel in May 1948, fighting broke out between Israeli and Lebanese forces. The fighting came to an end in March 1949 with an
armistice agreement, which reestablished the Palestine-Lebanon border as the Israeli-Lebanese border. 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, and 76 wounded. 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 Lebanon except for the city of
Tyre and its surrounding area. This operation is known in Israel as
Operation Litani, the stated objective of which was to clear out PLO bases in Lebanon south of the
Litani River, in order to better secure northern Israel and to support the Christian Lebanese militias in the
Lebanese Civil War - most notably the
Free Lebanon Army. 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. The Blue Line is based on the deployment of the IDF prior to 14 March 1978. It should not be confused with the
Green Line, established in 1949, which is the armistice line of the
1948 Arab–Israeli War, nor the
Green Line in Beirut during the violence of the 1980s. The 1949 line is in turn the same as the 1923 Mandate Line, which was the border between French- and British-mandated territory. See:
Paulet–Newcombe Agreement. Lebanon is a former
French mandate and Palestine / Israel a former
British mandate, per the
League of Nations. The 1949 agreement stated that the border would follow the 1923 line. In 1923, 38 boundary markers were placed along the 49 mile border and a detailed text description was published. The 2000 Blue Line differs in about a half dozen short stretches from the 1949 line, though never by more than 475 meters. Borders are usually negotiated between countries, and between 1950 and 1967 Israeli and Lebanese surveyors managed to complete 25 non-contiguous kilometers and mark, but not sign, another quarter of the international border. On 17 April 2000, when Israeli Prime Minister
Ehud Barak announced that Israel would begin withdrawing its forces from Lebanon, the Lebanese government did not want to take part in marking the border. The UN conducted its own survey based on the line discussed in
United Nations Security Council Resolution 425. On 25 May 2000 the government of Israel notified the Secretary-General that Israel had redeployed its forces in compliance with
Security Council resolutions 425. From 24 May to 7 June 2000, a UN
Special Envoy traveled to
Israel and
Lebanon to follow up on the implementation of the Secretary-General's May 22 report. The United Nations cartographer and his team, assisted by
UNIFIL, worked on the ground to identify a line to be adopted for the practical purposes of confirming the Israeli withdrawal. While it was agreed that this would not be a formal border demarcation, the aim was to identify a line on the ground closely conforming to the internationally recognized boundaries of Lebanon, based on the best available cartographic and other documentary evidence. On 7 June 2000, the completed map showing the withdrawal line was formally transmitted by the Force Commander of UNIFIL to his Lebanese and Israeli counterparts. Notwithstanding their reservations about the line, the Governments of Israel and Lebanon confirmed that identifying this line was solely the responsibility of the United Nations and that they would respect the line as identified. On 8 June, UNIFIL teams led by Lebanese Brig. General Imad Anka and Brigadier General Amin Htait began the work of verifying the Israeli withdrawal behind the line. The Secretary-General reported to the Security Council that Israel had withdrawn its forces from Lebanon on 16 June, in accordance with resolution 425 (1978), and met the requirements defined in his report of 22 May 2000. Namely, that Israel had completed the withdrawal in conformity with the line identified by the United Nations, the
South Lebanese Army militia had been dismantled, and all detainees held at Al-Khiam prison had been freed. The withdrawal line has been termed the Blue Line in all official UN communications since. == Border dispute ==