US responsible for Syria fallout: Iran

Iran's Foreign Ministry has condemned the US-led attacks on Syria, saying Washington and its allies would bear responsibility for the consequences in the region and beyond.

"Undoubtedly, the United States and its allies, which took military action against Syria despite the absence of any proven evidence ... will assume the responsibility for the regional and trans-regional consequences of this adventurism," Iran's Foreign Ministry said in a statement carried by state media.

"Iran is opposed to the use of chemical weapons on the basis of religious, legal and ethical standards, while at the same time it ... strongly condemns (using this) as an excuse to commit aggression against a sovereign state."

Iran has been Syrian President Bashar al-Assad's most supportive ally against insurgents throughout the conflict.

Iran-backed militias first helped his army stem rebel advances and, following Russia's entry into the war in 2015, turn the tide decisively in Assad's favour.

Analyst Hossein Sheikholeslam, a former Iranian ambassador to Damascus, told state television the attacks would help unite Syrians behind the government.

"These attacks will stabilise the Syrian government... and unite the different tribes in Syria as Syrians become aware of their honour and come to the defence of the independence, territorial integrity and the government of their country," Sheikholeslam said.