Syrian-Jordanian relations have fluctuated between normal diplomatic relations and armed confrontation. At times each side has attempted to subvert the other and has supported and provided refuge to the other's internal opposition groups. Jordanian interest in Syria began in 1921, when the founder of the Amirate of Transjordan, Amir Abdallah, sought to advance into Syria, from which his brother had been expelled by the French, and which he regarded as part of the promised Hashimite kingdom. Even as late as 1946, when both countries gained independence, King Abdallah did not abandon his plan to become king of Syria. Syria considered Abdallah's schemes for an expanded Hashimite kingdom as intervention in its domestic affairs and officially complained to the Arab League. During the 1950s, Syria mounted a propaganda campaign against Abdallah and granted political asylum to opposition elements from Jordan, including political asylum in 1957 to Jordanian Army officers and civilian politicians who had conspired to topple King Hussein. Tensions mounted in 1958 when Hussein's private jet en route to Europe was intercepted by Syrian MiGs and forced to return to Amman. Also, Syrian-trained groups infiltrated Jordan to carry out subversive acts, culminating in the August 1960 assassination of Jordanian Prime Minister Haza al Majali, whose killers escaped to Syria.

Syrian-Jordanian tensions were exacerbated in the late 1960s, following the rift between Jordan and the PLO, with Syria supporting the Palestinians against Jordan. In September 1970, Syria sent an armored division into Jordan to reinforce the Palestinian forces under attack by Hussein's army. By July 1971, Syria had broken off diplomatic relations with Jordan over the issue.

The October 1973 War resulted in a gradual improvement in relations, as Jordan contributed to the Syrian military effort. In 1976 Jordan was the only Arab country to support the Syrian invasion and subsequent role in Lebanon. However, another break between Syria and Jordan occurred in 1977, following Jordan's tacit support for Egyptian President Sadat's peace initiative. During this period Syria charged Jordan with harboring members of the Muslim Brotherhood, who had escaped from Syria. This charge led to new tension in December 1980, with military forces of both sides deployed along the border. As a counterweight to Syria, Jordan improved its relations with Iraq, and became one of its primary suppliers. In 1981 Jordan accused Syria of being behind the kidnapping of the Jordanian military attaché in Beirut and charged Rifaat al Assad, President Assad's brother, with masterminding a plot to assassinate the Jordanian prime minister. By the mid-1980s, rapprochement efforts were again underway (see Foreign Policy , ch. 4).

Data as of April 1987