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Russia is warning the U.S. against any “military intervention” in Syria over the government's alleged chemical attack against civilians this weekend, saying any such response would be “unacceptable” and lead to the “most serious consequences”.

The foreign ministry in Moscow also says in a statement on its website that allegations of the chemical attack are “fabricated,” suggesting the claims were invented by rebel forces and the Syrian Civil Defense known as the White Helmets.

“It is necessary to warn again that military intervention under invented and fabricated pretexts in Syria, where at the request of the lawful government there are Russian military personnel, is absolutely unacceptable and can lead to the most serious consequences,” the statement reads. “The aim of these false speculations, that have no basis, is to shield the terrorists and the irreconcilable radical opposition, who reject a political solution, at the same time while trying to justify possible armed strikes from outside.”

The alleged attack on Saturday killed 40 in the rebel-held town of Douma, multiple opposition and rescue groups including told The Associated Press, which was unable to independently verify the reports.

It came a year and a day after President Donald Trump ordered dozens of strikes on a Syrian regime air base for its alleged use of sarin gas on April 4, 2017, that killed approximately 100 people, according to the the State Department. More than 30 of the victims were children. The government of Syrian President Bashar al-Assad denied carrying out the attack.

PHOTO: This image released early Sunday, April 8, 2018 by the Syrian Civil Defense White Helmets, shows a child receiving oxygen through respirators following an alleged poison gas attack in the rebel-held town of Douma, near Damascus, Syria. (Syrian Civil Defense White Helmets via AP) More

President Donald Trump meanwhile blasted Russian President Vladimir Putin and the government of Iran for backing Assad, whom Trump dubbed "Animal Assad," in the country's years-long civil war.

Trump on Twitter called it a “mindless CHEMICAL attack” and blamed "President Putin, Russia and Iran" for backing the government of Syrian President Bashar al-Assad.

Many dead, including women and children, in mindless CHEMICAL attack in Syria. Area of atrocity is in lockdown and encircled by Syrian Army, making it completely inaccessible to outside world. President Putin, Russia and Iran are responsible for backing Animal Assad. Big price... — Donald J. Trump (@realDonaldTrump) April 8, 2018

....to pay. Open area immediately for medical help and verification. Another humanitarian disaster for no reason whatsoever. SICK! — Donald J. Trump (@realDonaldTrump) April 8, 2018

If President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago! Animal Assad would have been history! — Donald J. Trump (@realDonaldTrump) April 8, 2018

The State Department, while unable to confirm reports of chemical weapon use Saturday, called the alleged attack "horrifying."

"Reports from a number of contacts and medical personnel on the ground indicate a potentially high number of casualties, including among families hiding in shelters," Nauert said in a release. "These reports, if confirmed, are horrifying and demand an immediate response by the international community."

The United Nations also weighed in, saying that the alleged use of chemical weapons if true is "abhorrent."

"The Secretary-General is particularly alarmed by allegations that chemical weapons have been used against civilian populations in Douma," a spokesman for U.N. Secretary-General Antonio Guterres said in a statement. "While the United Nations is not in a position to verify these reports, the Secretary-General notes that any use of chemical weapons, if confirmed, is abhorrent, and requires a thorough investigation."

"It is critical that civilians be protected," the statement from spokesman Stephane Durjarric said. "There has also been shelling on Damascus city, reportedly killing civilians."

This photo released by the Syrian Civil Defense White Helmets, which has been authenticated based on its contents and other AP reporting, shows smoke rising after Syrian government airstrikes hit in the town of Douma, in Syria, Saturday, April. 7, 2018. (AP) More

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