The UN said sarin had been used in that attack, which killed hundreds of people in the Ghouta agricultural belt to the west and east of the capital.
The Syrian president has strongly denied his forces were behind the gas attack, although Israel, along with the USA and much of the global community, has accused the Syrian regime of carrying out the strike.
Speaking Wednesday evening on French TV, Foreign Minister Jean-Marc Ayrault said: "We will provide proof that the regime did indeed organize these strikes with chemical weapons". The implication is that Syria may be concerned about additional US strikes following the cruise missile attack earlier this month in retaliation for alleged Syrian use of sarin gas.
British Secretary of State for Foreign and Commonwealth Affairs Boris Johnson has said Britain could join US air strikes against the Bashar al-Assad's regime in Syria despite a previous vote in the parliament against it.
Israel has largely stayed out of the fighting, though it has carried out a number of airstrikes on suspected Iranian weapons shipments it believed were bound for the Lebanese militant group Hezbollah.
President Donald Trump was never going to be involved in Syria's war, but 72 hours after Assad's chemical strike on his own people, Trump was dispatching 60 tomahawk missiles onto one of Syria's six military airfields. The US attack killed several Syrian soldiers and nearly completely destroyed the base.
GETTY GOT YOUR BACK Boris said Britain would find it hard to say no to Trump
Meanwhile, the presidential advisor said that the USA is in a state of declination, while Russia, China and India are rising high. The strike aimed to destroy airplanes as well as prevent take-offs and landings. Russian Federation has cautioned that the incident may have been a false flag operation meant to provoke a United States attack against Syrian government forces. The Trump Administration responded by denouncing Syria's use of chemical warfare and Russia's attempt to shield them.
The state of the Syrian government's chemical weapons program has been the subject of fierce scrutiny in recent weeks, after a deadly chemical attack in northern Syria earlier this month killed more than 80 civilians.
On Tuesday morning a residential district in Chan Sheikhun in Idlib province was bombed and poison gas was released.
Islamic State group-inspired attacks have killed at least 235 people in France since January 2015, by far the largest casualty figure of any Western country.
Assad agreed in 2013 to declare and dispose of all his chemical weapons under United Nations supervision, but his forces have repeatedly been accused of using them since then.
In a 2013 agreement brokered by Russian Federation and the United States, Syria agreed to destroy its chemical weapons.
However, there were doubts that the regime had handed over all the chemical weapons it possessed and a belief that it did not declare all of its production facilities, some of which are feared to have been taken over by Isis.
Barack Obama to give 1st speech since leaving office in Chicago
Bush who resisted pressure from his aides and supporters to criticise his successor during the months after Obama took office. Obama will return to public life on Monday after spending weeks vacating in French Polynesia.