Macron, criticised by the far-left and far-right and part of the conservatives over the attacks, said France, Britain and the United States had "complete worldwide legitimacy to act".
Macron said during an interview on French television that France has "proof" that Syrian President Bashar al-Assad's regime used chemical weapons.
"We convinced him it was necessary to stay for the long term".
Assad said Thursday that Western threats to strike Syria are based on "lies" and seek to undermine his forces' advances near Damascus.
French President Emmanuel Macron said on Saturday (April 14) that he had ordered a military intervention in Syria alongside the United States and Britain in an attack on the chemical weapons arsenal of the country's regime.
"We also persuaded him that we needed to limit the strikes to chemical weapons (sites), after things got a little carried away over tweets", he said.
"Whenever the Syrian army achieves victory in the field, some western countries rise their voices and intensify their movements in an attempt to change the track of events", Assad said, according to SANA.
Macron confirmed that he will visit St. Petersburg, Russia, in May.
Macron previously vowed to launch military action if France had evidence of chemical weapons being used.
The U.S. -led operation won broad Western support. "They have not used chlorine themselves, but they have methodically contributed to the worldwide community's powerlessness to prevent the use of chemical weapons by diplomatic means", he said.
Russian Federation has military forces, including air defenses, in several areas of Syria to support Assad in his long war against anti-government opposition forces. "Everyone knows there is only a solution to the conflict in Syria with Russia", Maas said.
The US and its allies, including the United Kingdom, have been considering whether to hit Syria over the suspected poison gas attack that medical relief organisations say killed dozens of people in the rebel-held town of Douma near Damascus on Saturday. "This is not about intervening in a civil war".
Macron also offered to play the role of intermediary between the United States and Russian Federation.
The strike has been furious condemned by Syrian ally Russian Federation, who attempted to bring a motion in the United Nations Security Council on Saturday to denounce the "aggression against the Syrian Arab Republic by the U.S. and its allies".
Syria has said all claims of involvement in the attack are false.
Asked if using military force would restore peace, Macron said that "France is the country that has been the most active in terms of diplomacy and humanitarian aid in recent months, and we came at a time when this strike was essential to give credibility to our community". In fact, Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff, said no additional attacks were planned.