Russian Foreign Minister Sergey Lavrov said on Tuesday that U.S. "threats" and "use of force" against the Syrian armed forces were "very alarming".
"As you know, there were not only [the U.S.] threats, but also there was the specific use of force in the area," Lavrov was quoted as saying by the official TASS news agency.
Lavrov said the situation was "very alarming", adding: "It directly affects the sovereignty of Syria. Of course, these issues need to be settled, which is what our military is currently engaged in."
The U.S.-led anti-Daesh coalition on May 18 struck forces allied to Syrian President Bashar al-Assad that "posed a threat to U.S. and partner forces" in the southeastern city of al-Tanf.
This was the second time that Washington used military force against Syria after Donald Trump was sworn in as U.S. president late January.
Lavrov said Moscow would welcome the U.S. involvement in order to avoid incidents and coordinate the parameters of "de-escalation zones" in Syria.
On May 4, Russia, Turkey and Iran signed a deal in the Kazakh capital, Astana, to establish "de-escalation" zones in Syria.
During the six-year conflict, the Assad regime has been regularly accused by numerous international actors of targeting Syrian civilians with chemical weapons.