Syrian Reconciliation Minister Ali Haidar's car came under fire Saturday near the coastal area of Tartous, Syrian activists and state media reported, but he was not in the vehicle at the time of the ambush, dpa reported.
Syria's state television said Haidar's driver was killed.
An eye specialist by training, Haider is the leader of the Syrian Social Nationalist Party, one of the Damascus-based opposition parties tolerated by the regime of Syrian President Bashar al-Assad. He was appointed minister in 2012.
Haider's son was killed last year when his car was ambushed by rebels in the central province of Homs.
Elsewhere in Syria, extremist rebels from the Islamic Army group and the al-Qaeda-linked al-Nusra Front have taken control of a major oil field in the eastern province of Deir al-Zour, an opposition watchdog said.
"Fighters from al-Nusra and other Islamist groups have taken the al-Omar oil field in Deir al-Zour following heavy battles overnight," the Britain-based Syrian Observatory for Human Rights said.
The battles prompted government troops to withdraw from the area, according to the Observatory.
Videos posted online showed opposition fighters around the entrance of the field. Rebels also claimed that they have seized seven tanks from regime forces.
Syria's oil sector has been at standstill since the crisis erupted. Crude oil production that was at 380,000 barrels per day (bpd) prior to the conflict has fallen to 20,000 bpd, according to Syrian oil experts.
The Observatory said al-Omar oil field produces some 75,000 bpd.
Much of Syria's oil-rich territory - located mostly in the east and northeastern part of the country - are now in the hands of the rebels.
The conflict in Syria, which began with anti-government protests in March 2011, has left more than 100,000 people killed, according to UN estimates.
The Observatory said Saturday that 40 people were killed when Syrian jets raided different areas in the northern province of Aleppo.