The launch of the missiles was ordered by the president in retaliation for a regime-led chemical weapons attack that killed scores of civilians on Tuesday.
Mr Ayrault told Reuters and France Info radio said: “A signal was sent, because yet again a red line was crossed by Bashar al-Assad."
He added that he has been informed of the strikes “during the night” by US Secretary of State Rex Tillerson.
Donald Trump's missile strike on Syria should be seen as a ‘WARNING’ says French foreign minister
Here, we have an action that is a sort of condemnation, through military strikes on a military base, of what this criminal regime is doing
The foreign minister added that he did not think that Washington wanted to continue its strikes and that the attack on the Assad-controlled airbase had been a “warning”.
He said: “Here, we have an action that is a sort of condemnation, through military strikes on a military base, of what this criminal regime is doing.
“The use of chemical weapons is appalling, but it’s also a terrible reality and it cannot go unpunished because it is a war crime."
Mr Ayrault has said that the missile strikes was a form of 'condemnation'
Mr Ayrault also said that Russia and Iran – Syria’s allies – had to understand that supporting Mr al-Assad “made no sense”, and urged Moscow to back a UN Security Council resolution that would help pave the way for peace in Syria.
He said: “Peace negotiations (are going on) for a political transition, to rebuild the country and enable the return of refugees and that will not happen with Mr al-Assad.
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“I will tell the Russians: 'Stop playing. Stop hesitating and pretending. Play your role and implement resolution 2254'(the UN resolution that sets out a roadmap for peace talks).”
Celebrities and Politicians React to Trump's Missile Attack on Syria Fri, April 7, 2017
Following news of the attack, celebrities and politicians expressed their thoughts on social media
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Trump ordered a massive military strike against a Syria
The left-wing minister added that France had no intention of entering the conflict between the Syrian regime and rebels, and that the country’s sole focus at present was to help the US-led coalition crush Islamic State.
The US attacked the Shayrat airbase in Homs province early on Friday morning, which is the site from which the chemical attack in Idlib that killed more than 70 is believed to have been launched.
The missile strike was the first direct assault on the Syrian regime in more than six years of civil war.