President Hafez al Assad of Syria made a rare foray abroad yesterday to attend the state funeral in Amman of his "old enemy", King Hussein.
For years, relations between the two countries were strained, with Mr Assad suspecting the monarch of maintaining secret ties with Israel while King Hussein was wary of Syria's territorial ambitions.
When Jordan decided to go it alone and signed a peace treaty with Israel in 1994, the Syrian President fumed, charging that Jordan had committed a "grave offence against united Arab efforts to reach a comprehensive peace".
And Mr Assad branded Jordan's decision to grant Israel a 25-year lease of some Jordanian territory as an "impious act".
King Hussein always suspected the Syrian leader of wanting to rule over a "Greater Syria" that would comprise Syria proper, Lebanon, Palestine and Transjordan. For his part, Mr Assad never forgave King Hussein for making a secret visit to Tel Aviv in 1973 to warn Israeli leaders of an imminent Syrian-Egyptian military offensive - although Syria and Jordan had fought side-by-side in the 1967 Arab-Israeli war.
The Palestinian issue was another point of contention between Amman and Damascus. In August 1971, Syria severed diplomatic relations with Jordan and closed its air space to Jordanian aircraft, one month after the end of a bloody crackdown by the Jordanian army against the Palestinian resistance. The crackdown was launched in September 1970 - known as Black September - and lasted until July 1971.
When Syrian troops drove the Palestinian leader, Mr Yasser Arafat, from Lebanon in 1983, King Hussein welcomed Mr Assad's rival with open arms in Jordan and even went on to sign a peace initiative with him in 1985. The pact lasted one year.
During the 1980 Iran-Iraq war, Jordan sided with Baghdad while Syria gave Iran undivided support. During the 1991 Gulf War, Syria joined the US-led coalition of Arab and Western forces to drive Iraqi troops from Kuwait while Jordan broke ranks with the Arab world and took sides with Iraq.
Syria and Jordan also agreed to disagree over Turkey. Damascus has long accused Ankara of refusing to give it an equal share of water from the Euphrates river, which has its source in Turkey and runs through Syria and Iraq.
Syria has also lambasted Turkey for striking a military alliance with Israel while Jordan assisted as an observer to joint Israeli-Turkish manoeuvres in the Mediterranean in 1998. The common border they share has also been at the centre of their stormy relations.
Damascus accused Jordan in the 1980s of allowing Muslim Brotherhood militants to cross the border to carry out attacks in Syria while Amman charged that Syria allowed Palestinian guerrillas across the border for similar reasons.
But the two leaders pledged to bury the hatchet during a "reconciliation" meeting sponsored by the Egyptian President, Mr Hosni Mubarak, on the sidelines of the 1996 Arab summit in Cairo.
Relations did not warm up, however, despite a visit by King Hussein to Syria in August, 1996.
In November, 1998, Jordan accused Syria of holding hundreds of Jordanian prisoners. Nevertheless, Mr Assad telephoned King Hussein on January 19th to inquire about his health when the monarch returned home to Jordan after a six-month battle with cancer in a US clinic.
And without previous notice President Assad flew into Amman for the funeral after postponing until tomorrow a referendum which was to be held yesterday in Syria to reconfirm Mr Assad as President. He also declared three days of mourning.