The Syrian Army and its allies recaptured an oil field from the Islamic State extremist group near the eastern city of Deir al-Zour on September 9, state TV reported.
The Teym oil field is located in a desert south of Deir al-Zour.
Government forces also captured part of a main highway running from Al-Zour to the city of Al-Mayadeen, downstream along the Euphrates River, where IS militants have retreated, the Syrian Observatory for Human Rights monitoring group said.
That advance would block potential IS reinforcements from Al-Mayadeen, which is close to the Iraqi border.
The oil-rich province of Deir al-Zour has become the latest epicenter of the war against IS.
This week, Syrian troops and their Iranian-backed allies reached Deir al-Zour, breaking a nearly three-year siege by IS on government-held parts of the city. Government forces are trying to reach a nearby air base, still surrounded by IS militants.
Recent gains have put pressure on IS, which currently holds much of Deir al-Zour Province and half the city, as well as a pocket of territory near Hama and Homs in the west of Syria.