Syria's military and allied fighters have made new advances against the Daesh Takfiri terrorist group and other militants in the country's strategic southern desert.

Various sources, including opposition media channels, confirmed on Saturday that the government and allied troops had secured a large territory in the Syrian Desert. They said the region covered some key areas that used to be under the control of Daesh and other militant groups that enjoy support from the West.

The Syrian Central Military media said 5,000 kilometers (3,100 miles) in the desert area were secured in the multi-pronged operation, which began more than two weeks ago. The gains restore the government's control over mineral and oil resources, including the key phosphate mines in Khneifes, a major source of revenue for Daesh.

Other sources said Syrian forces also recaptured al-Ilianiya, an area controlled by US-backed militants near the border with Jordan. The Britain-based Syrian Observatory for Human Rights, which advocates Syria’s opposition, said Syrian forces had secured a total of 6,000 kilometers (3,700 miles) in the desert since the offensive began earlier this month.

Syrian government forces secure a road for a military convoy in the desert area of Saba' Biyar in southeastern Syria near the border with Iraq on May 10, 2017, amid clashes in the region. (AFP photo)

Experts say gains made on Saturday would significantly boost the morale of the government forces in the battle against militants while they could hugely facilitate the advance toward the province of Dayr al-Zawr, where Daesh holds a grip. The advances also widen the government's control south of Palmyra in Homs province while the highway linking Palmyra to the capital Damascus would also be secured.

The advance could apparently irk the United States, which had deployed troops to southeastern Syria to support militants. Washington even launched an airstrike on a convoy and a base of Syrian fighters deployed to the area on May 18. US officials said after the attack that they were deeply concerned about the safety of troops and allies who are allegedly fighting Daesh in southeastern Syria.