Arab Deterrent Force

The Arab Deterrent Force (ADF; Arabic: قوات الردع العربية) was an international peacekeeping force created by the Arab League in the extraordinary Riyadh Summit on 17–18 October 1976, attended only by heads of state from Egypt, Kuwait, Lebanon, Saudi Arabia, and Syria. It decided to transform the 'token' Arab Security Force into the Arab Deterrent Force. A week later, the conclusions of the Riyadh Summit were endorsed and implemented by the Arab League's Cairo summit on 25–26 October 1976.

As the Lebanese Civil War escalated in 1976, the Arab League created an intervention force composed almost entirely of Syrian forces with token contributions from other Arab states, including Sudan, Saudi Arabia and Libya. Although nominally present at the behest of the government of Lebanon, the force was under the direct command of Syria. The ADF initially consisted of 30,000 troops of which 25,000 were provided by Syria. In the spring of 1979, after the Arab League had extended the mandate of the Arab Deterrent Force, the Sudanese, the Saudis and the United Arab Emirates troops departed Lebanon, the Libyan troops were essentially abandoned and had to find their own way home (if at all), and the ADF thereby became a purely Syrian force (which did include the Palestinian Liberation Army (PLA)).

The ADF mandate was to deter the conflicting sides from resorting to conflict again, including the tasks of maintaining cease-fire, collecting heavy weapons and supporting the Lebanese government in maintaining its authority.

Robert Fisk wrote:

..Since the summer of 1976, the Syrians had controlled the Bekaa Valley. The headquarters of their 'Arab Deterrent Force' was at the Bekaa market town of Chtaura and their troops were billetted all the way up the valley, around the Greek Orthodox town of Zahle - where Cody and I had seen the Syrians and Phalangists cooperating in 1976 - at the airbase at Rayak, in Baalbek and Hermel.

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