Troops began evacuating four positions on Monday and scaled back their forces in Qolaiaat, Akkar, and Baalbek in the eastern Bekaa Valley.
Soldiers also abandoned buildings on the Aaramoun hills, about 10 km south of Beirut.
No military convoy, however, had crossed the Lebanese-Syrian border on the Beirut to Damascus road since Monday night, suggesting some troops were being redeployed inside Lebanon.
Quoting a Lebanese military source, the pro-Syrian daily As-Safir said the partial pullout was "part of a plan for redeployment agreed in January during top-level military meetings".
The comment appeared to rule out suggestions that the pullback was the result of pressure from the United States, which has called on Damascus to withdraw and branded its military presence in Lebanon an "occupation".
In what has led analysts to suggest that Syria may be next on the US so-called “hit list”, Washington has warned Syria in recent months not to interfere in Iraq and to support the "road map", an international plan to revive the flagging Israeli-Palestinian peace process.
"US not calling shots''
Pro-Syrian Lebanese MP Nasir Qandil rejected the idea that the pullout was the result of the United States calling the shots, pointing out that Washington has repeatedly praised Damascus for cooperating in the war against terror.
"Syria is redeploying its troops as was agreed in the Taif accord and which it began two years ago, before these pressures," he said on Future Television.
Under the terms of the Taif agreement of 1989, which brought an end to the Lebanon’s 15-year civil war in 1990 - Damascus should have pulled out in 1992.
In May, Cardinal Nasrallah Sfeir, leader of the Maronite Church – the largest Christian community in Lebanon – advanced caution over US and French intervention in favour of a Syrian withdrawal from Lebanon.
Less than 20,000 Syrian troops – compared to more than 35,000 in 2000 – are now stationed in Lebanon, which they first entered when they intervened in the civil war in 1976.
Lebanese newspapers in June for the first time reported that all Syrian troops could be withdrawn from Lebanon by 2004.