Syrian government forces withdrew from the key city of Homs on Dec. 7, abandoning the city to advancing rebel units after less than a day of fighting.
The move effectively cuts off Syrian leader Bashar al-Assad from access to the coast and Russia's air and naval bases on the Mediterranean Sea.
Homs is the latest major Syrian city to fall to rebel forces in recent days. Anti-government fighters launched a rapid advance in late November, gaining control of Aleppo and Hama. Rebels are reportedly now poised to strike Damascus.
U.S. officials told CNN on Dec. 7 that Assad's regime could collapse "by next weekend."
The Syrian government claims that Assad has not left Damascus and that the army is reinforcing defenses around the capital.
Homs is located between Damascus, Syria's capital, and the Mediterranean coast — where Russia maintains its Khmeimim Air Base and Tartus Naval Base.
Russia, Assad's key military backer, has reportedly launched multiple airstrikes against Syrian cities in an effort to combat the rebel advance.
Satellite imagery suggests that Russia withdrew all naval assets from the Tartus port when rebel forces captured Aleppo. The port is Russia's only naval base in the Mediterranean.
The fall of Assad threatens to diminish Russia's regional and global standing.
Russia deployed troops to Syria in 2015, providing support to the Assad regime against multiple anti-government forces. Damascus has supported the Kremlin throughout the full-scale invasion of Ukraine.