Russia's envoy to the UN has accused the US of violating international law by carrying out airstrikes on Syria. US envoy Nikki Haley said the strikes were justified and threatened further action.
Russia's deputy envoy to the UN, Vladimir Safronkov, on Friday warned that the US' airstrikes on a Syrian base could have damaging consequences on regional and global stability.
"The United States attacked the territory of sovereign Syria," Safronkov said during an emergency UN Security Council meeting in New York. "We describe that attack as a flagrant violation of international law and an act of aggression."
The comments come after the US launched a barrage of Tomahawk missiles on a Syrian airbase in Shayrat in the early hours of Friday morning. The White House said the attack was in retaliation to an alleged chemical strike earlier this week on the Syrian rebel-held town of Khan Sheikhoun that killed more than 80 people.
Both the regime of Syrian President Bashar al-Assad and its allies in Moscow have denied perpetrating the attack, saying any nerve agents released must have belonged to the rebels and could have been hit by a conventional strike.
Report: US investigating Russian involvement in gas attack
The Associated Press (AP) press agency reported that US military officials were probing whether Russia had participated in the alleged chemical attack on Khan Sheikhoun.
A US official, speaking to AP on condition of anonymity, reported of a Russian or Syrian drone seen hovering over the site of Tuesday's attack and was seen again later as citizens scampered into a nearby hospital for treatment. The hospital was reportedly bombed shortly afterwards in what may have been a bid to cover up the attack.
The US military said it was still reviewing the evidence.
Merkel: US attack on Syria is 'understandable'
Russia vows to bolster Syrian air defenses
Following Friday morning's attack, Russian officials promised to strengthen the Syrian army's air defenses to protect both Syrian and Russian military infrastructure.
Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov said that a "complex of measures" designed to strengthen the Syrian army's defense capabilities would be implemented to help "protect the most sensitive Syrian infrastructure facilities."
Russia had previously supplied the Assad regime with state-of-the-art S-300 and S-400 anti-aircraft missile systems.
Konashenkov also said that Russia's own air defense systems were reliably protecting its warplanes at the Hemeimeem air base in the Syrian province of Latakia, as well as on its navy outpost in Syria's Mediterranean port of Tartus.