The bomb attack that killed nine soldiers in Lebanon was a message to the army and aimed at undermining a landmark visit by President Michel Suleiman to former powerbroker Syria, analysts said.

The soldiers were among 14 people killed in Wednesday's morning rush hour blast at a bus stop frequented by troops in the northern port of Tripoli, Lebanon's second city.

The city has been rocked by recurrent violence since last year, when the army fought a 15-week battle with militants of the al-Qaida inspired Fatah al-Islam in the Nahr el-Bared Palestinian refugee camp on Tripoli's outskirts.

Oussama Safa, head of the Lebanese Centre for Policy Studies, said the attack could have been one of a series he saw as retribution for the army's crushing of Fatah al-Islam last year.

The Lebanese forces have come under repeated attack since those battles that left 400 people dead, including 168 soldiers.

"I see this within a spate of attacks against the army that could be reprisal attacks for the army's crushing of Fatah al-Islam last year," said Safa.

In December the head of the army's military operations, General Francois el-Hajj, was killed in a massive bomb attack and just over a month later Major Wissam Eid, a top intelligence officer, was killed in similar circumstances.

MP Ahmed Fatfat saw in Wednesday's attack "a clear message to the army, warning it against playing an effective role," in restoring law and order across Lebanon.

The bombing was the deadliest attack since Lebanon's Western-backed anti-Syrian ruling majority sealed a power-sharing agreement with the Syria- and Iran-backed opposition in Doha, Qatar, in May.

The deal paved the way for the election of Suleiman, the former army chief, and the formation of a national unity government -- developments widely seen as only possible with Syria's approval.

The bombing, which has not yet been claimed by any group, also came one day after the national unity cabinet secured a much-delayed vote of confidence from parliament.

Analysts and politicians also saw in it a clear political message aimed at undermining Suleiman's visit Wednesday and Thursday to Damascus whose goal is to redefine relations between the two neighbors after decades of rocky and uneven ties.

The timing of the attack reflects its aim "to prevent the improvement of Lebanese-Syrian relations," said parliament Speaker Nabih Berri, a stalwart of the pro-Syrian opposition.

Syria dominated Lebanon politically and militarily for nearly three decades until April 2005 when it withdrew its troops from Lebanon following international pressure.

The pullout came two months after the assassination in a massive Beirut bomb blast of Lebanese ex-premier Rafik Hariri, for which Damascus has denied any responsibility despite accusations by Lebanese anti-Syrian groups.

Wednesday's bombing "may hasten Suleiman's demand for faster stability. That will probably mean that a fast appointment of a commander-in-chief and heads of the security agencies," according to Safa.

"For that, they will need a kind of green light from Damascus," he said.

The 64,400-strong army has been without a commander-in-chief since Suleiman's election as president. Other top security positions also need to be filled.

These positions have been left empty as a result of a debilitating political crisis that lasted over 18 months and pitted the ruling majority against the Hizbullah-led opposition.

The crisis turned violent in May when Hizbullah took over swathes of mostly Muslim west Beirut amid fighting that left 65 people dead.(AFP)