Syria is reportedly moving troops to a desert region near its border with Iraq and Jordan amid reports that US and allied forces are consolidating positions in the area for a possible ground invasion.
Militant sources and commanders said Monday their intelligence showed that hundreds of Syrian troops and their allies with tanks and heavy equipment had moved in the last few days to the town of Saba'a Biyar.
The remote town near the strategic Damascus-Baghdad highway was captured by the army last week as they seek to prevent areas left by Takfiri terrorists from falling into the hands of Western-backed FSA militants.
"They have sent big reinforcements from artillery, to tanks and armored vehicles," FSA spokesman for the so-called Southern Front Issam al-Reis told Reuters.
US special forces operate and train FSA militants at the Tanf base near the Iraqi border in the area which is known as the Syrian Badia, meaning desert in Arabic.
The base is being expanded to become a launching pad for operations in the province of Dayr al-Zawr that straddles Iraq, Reuters cited regional intelligence sources as saying.
Syrian media on Sunday said government forces have made fresh gains against terrorists in Dayr al-Zawr.
Army units clashed with terrorist groups affiliated with Daesh in the province, leaving a number of terrorists killed and their fortifications and hideouts destroyed.
Last week, about 7,400 troops began conducting military exercises known as Exercise Eager Lion in Jordan, in what was described as the largest and most complex of their kind conducted jointly with the US.
The exercises prompted concerns that Washington and its allies were attempting to stage a major intervention to undermine recent gains made by the Syrian military against Daesh terrorists.
As the Syrian military began a new eastward push to drive out Daesh from Dawr al-Zawr, Foreign Minister Walid al-Muallem warned Jordan against getting involved without Syria's permission.
"If the Jordanian forces entered without coordination with the Syrian government they will be considered as hostile forces," Muallem said.
In addition to the large US presence on the Jordanian side of the border, US special forces were also spotted inside Syria, training a group of militants called Mughawir al-Thowra, the Newsweek magazine reported.