BEIRUT (AP) -- Syrian troops and allied militia have pushed back Islamic State militants, rebels and U.S-backed opposition fighters in a wide offensive in the country's strategic southern desert, the government-controlled media and a war monitor said Saturday.
With the new advances, the government and allied troops secured their hold of a strategic juncture in the Syrian desert, restoring their control of mineral and oil resources. The gains also aid government plans to go after IS militants in Deir el-Zour, on the border with Iraq.
The state-controlled Syrian Central Military media said the new advances widen the government's control south of Palmyra in Homs province and secure the highway linking the ancient city to the capital Damascus. The gains also secure the phosphate mines in Khneifes, once controlled by the Islamic State group.
The area was the backyard of territories once tightly controlled by IS militants, and served as a route linking Palmyra and the borders with Jordan, their de-facto capital Raqqa, and Deir el-Zour near the border with Iraq.
The large swath of desert, which had been divided between IS and rebel control, also abuts the capital Damascus and its suburbs.
The offensive has been ongoing for days and caused tension in the area, prompting a U.S. airstrike on Syrian government and allied troops near the border with Jordan.
The Syrian Central Military media also said the new advances, which secure about 5,000 kilometers (3,100 miles) in the desert area, have also successfully isolated anti-government rebel fighters in the desert area east of Damascus, denying them advances toward the strategic Homs desert area.
The opposition Britain-based Syrian Observatory for Human Rights said the government and allied troops have also advanced toward al-Ilianiya, an area controlled by Syrian opposition fighters, backed by the U.S. and western countries, in the desert near the border with Jordan.
The advances also open the road for the government and its allied troops toward the IS-stronghold of Sukhna, a key node in the push toward the province of Deir el-Zour, which straddles the border with Iraq, said Mozahem al-Salloum, of the activist-run Hammurabi Justice News network that tracks developments in eastern Syria.
The crowded battlefield has been a scene of tension in recent weeks, as the government and allies pushed their way further south where rebel fighters backed by the U.S. military also operate. U.S. warplanes struck a convoy and a base of Syrian and allied troops on May 18, in the first such battlefield confrontation between American and Syrian forces since the conflict began in 2011.
U.S. officials said the Syrian advances "posed a threat" to its troops and allies fighting the Islamic State group in the area.