The Russian Embassy in Washington says it has warned top U.S. officials not to engage in any "unjustified and illegal act of aggression," in response to recent U.S. warnings that it will retaliate against any new chemical-weapons attacks by the Syrian government.
"We warned the United States against yet another unjustified and illegal act of aggression in Syria. Escalation of tensions in Syria is not in anyone's national interests," the embassy said in a statement posted late on August 29 on its Facebook page.
The statement said the warning against any U.S. strikes against the Syrian government, which is Russia's ally, came earlier this week at a private meeting Russian Ambassador Anatoly Antonov requested with U.S. Assistant Secretary of State for Near Eastern Affairs David Satterfield and Washington's new representative for Syria, Jim Jeffrey.
U.S. President Donald Trump has twice ordered air strikes against alleged Syrian chemical weapons facilities, both after incidents in which dozens of Syrian civilians were killed by alleged toxic gas attacks by Syria's Air Force.
Russia's warning against further U.S. strikes came as UN Secretary-General Antonio Guterres joined Western powers in urging Syria not to use chemical weapons again after several previous incidents documented by the UN.
"Any use of chemical weapons is totally unacceptable," Guterres' spokesman said.
Both Syria and Russia have denied that Damascus uses chemical weapons, and they have sought to cast blame for documented chemical incidents on Syrian rebels fighting the government in a seven-year civil war that has killed more than 400,000 people.
The Russian Embassy said that Antonov in his meeting with Satterfield "urged Washington to immediately provide facts that may support this attempt to once again propagate the issue of chemical weapons use by Damascus."
"We have expressed most serious concern about the U.S. side's signals indicating that new strikes on Syria are being prepared under the pretext of possible use of 'chemical weapons' by Syrians. We conveyed our serious concern about those developments," the embassy said.
The exchange of warnings occurred as Syrian and Russian forces have been gathering for what Western powers say appears to be a major planned assault to regain control of Idlib Province, the last major stronghold of Syrian Sunni rebels.
Russian Foreign Minister Sergei Lavrov on August 29 described the thousands of rebels in the province -- many of whom were transported there under safe passage agreements brokered by the Russian military in exchange for their surrender in other parts of Syria in the last year --as "a festering abscess" that needs to be "liquidated."
With more than 3 million people living in the province bordering Turkey, Guterres on August 29 repeated the UN's warning "about the growing risks of a humanitarian catastrophe in the event of a full-scale military operation in Idlib Province."
The UN estimates that a major offensive in the Idlib area, where displaced people already make up half the population, risks forcing another 700,000 Syrians from their homes.
Guterres appealed to the Syrian government, Russia, and all other parties "to exercise restraint and to prioritize the protection of civilians."
Guterres also urged the guarantors of a so-called Astana peace process -- Turkey, Iran, and Russia -- to step up their efforts "to find a peaceful solution to the situation in Idlib."
Turkey backs many of the Sunni rebel groups in Idlib and also has a small military presence in the province, while Iran, like Russia, is backing the Syrian government in its effort to reassert control over the territory.
Lavrov said Russia has a "political understanding" with Turkey on the need to distinguish between the Syrian "opposition" -- apparently, the groups that Turkey supports -- and people he described as "terrorists" in Idlib that are targets to be "liquidated."