TEHRAN, April 14 (Xinhua) -- Iran's Foreign Ministry on Saturday strongly condemned the U.S., Britain and France for launching airstrikes against Syria.

"This invasion is a clear violation of international regulations and undermining Syria's national sovereignty and integrity," the ministry said in a statement.

Earlier Saturday morning, the U.S., in cooperation with Britain and France, attacked Syrian military facilities reportedly related to Syria's chemical weapons capabilities.

The U.S. and its allies have invaded Syria "without any proof" of the use of chemical weapons and "they are responsible for their adventurism," the statement said.

The strikes on Syria have been carried out to boost the morale of the terrorist groups following their defeat by the Syrian army, it said.

"However, the Syrian people will annul the plots to change the situation in favor of the terrorist groups," it added.

The U.S. and its allies launched the latest airstrikes to retaliate for the alleged use of chemical weapons by Syrian troops in the April 7 attack against the rebel-held town of Douma near Damascus. The Syrian government has strongly denied the allegations.

U.S. President Donald Trump ordered a similar airstrike against Syria last year to punish the Syrian government for another alleged use of chemical weapons against civilians.