Russia has accused the United States of supporting Islamic State (IS) militants in Syria, enabling them to mount counteroffensive attacks there.
The Defense Ministry made the accusation on October 4 as Russian-backed Syrian government forces and fighters backed by the United States are racing to capture territory from the IS extremist group.
As the separate campaigns are being waged within close proximity of one another, the Russian and U.S. militaries have traded charges that their troops or allies were endangered or struck by the other side's forces.
Russian Defense Ministry spokesman Igor Konashenkov said that a series of attacks launched by IS militants on Syrian government forces came from an area around Al-Tanf near the border with Jordan where a U.S. mission is located.
Konashenkov said the attacks took place last week near Al-Qaryatayn in the Homs Province and a highway linking the central city of Palmyra and Deir al-Zor to the east.
A fighter for the Free Syrian Army loads a US-made M2. The YSA is supplied by the US, but opposes the YPG, also supplied by the US.
The spokesman said that the attackers had the precise coordinates of the Syrian government forces, which could only have been obtained through aerial reconnaissance.
"If the U.S. side views such operations as unforeseen 'accidents,' Russian aviation in Syria is ready to begin the complete eradication of all such 'accidents' in the zone under their control," Konashenkov warned.
"The main thing preventing the final defeat of [the IS group] in Syria is not the terrorists' military capability but the support and pandering to them by our American colleagues," he added.
It is the latest of a series of accusations traded as Russian-backed troops loyal to Syrian President Bashar al-Assad and the U.S.-allied, Kurdish-led Syrian Democratic Forces battle IS fighters in the eastern province of Deir al-Zor near the Iraqi border.
Moscow and Washington held a first-ever meeting between their generals last month to try to prevent accidental clashes between the two sides, but reports of deaths in continuing clashes suggested the problem was not resolved.