The Tanf military base is a lonely, desert oasis roughly 10 miles inside Syria near the Jordan border, and about 100 miles south of Palmyra.
I've said for more than a year that there is no justifiable reason for our military base at Al-Tanf, except as a foothold for invasion. Syrian rebels have used the area to launch attacks against government forces, and Russia's patience with the current situation has run out.

Russia has warned the US that its military and allied Syrian forces are ready to attack a key US-held base near the borders of Syria, Jordan, and Iraq, US defense officials said in a CNN report published on Thursday.

The Kremlin is said to have accused the US-led coalition base At Tanf of protecting nearby militants, with Russia delivering two warnings in the past week, CNN said, citing US officials. At Tanf, from which a coalition of dozens of US troops and Syrian rebels launch operations against the Islamic State terrorist group, is seen as a critical location within the scope of Iranian, Syrian, and Russian influence in the region.

"We have absolutely advised them to stay out of At Tanf," a US official told CNN. "We are postured to respond."

"The United States does not seek to fight the government of Syria or any groups that may be providing it support," another official added. "However, if attacked, the United States will not hesitate to use necessary and proportionate force to defend US, coalition, or partner forces."

The Pentagon has taken the threats seriously enough that it has begun preparations for the attack.

The U.S. has gone so far as to deny that the Al-Tanf base is protecting militants.

"There is no terrorist camp within the al-Tanf de-confliction zone, which runs in a 55k diameter around the Coalition's al-Tanf Garrison," the spokesperson said when asked about the militants' allegations.
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The allegations the spokesperson mentioned were made by a group of militants who were recently captured in battle. As the Russian Defense Ministry's Center for Syrian Reconciliation stated Saturday, this group revealed that they were members of the Lions of the East group and admitted that they have a training camp near the US military base in al-Tanf.

The jihadist rebels seem to have not gotten the memo that they don't exist in the Al-Tanf area because they proudly announced their accomplishments there just the other day.

US-trained Syrian rebel fighters have reputedly repelled an attack launched by the Syrian Army near al-Tanf base in south-east Syria.

Revolutionary Commando Army (aka Maghawir al-Thawra), claimed they – supported by the US-coalition forces – have managed to foil the Syrian forces’ assault on the 55 km de-confliction zone around the Tanf base.