French President Emmanuel Macron warned on Tuesday that his country was prepared to launch strikes against the Syrian regime if evidence revealed that it had carried out chemical weapons attacks against civilians. "We will strike the place where these launches are made or where they are organized," Macron told the presidential press corps. "But today our services have not established proof that proscribed chemical weapons have been used against civilian populations," he added. "As soon as such proof is established, I will do what I said," Macron warned, while adding that "the priority is the fight against the terrorists". Regarding the Syrian regime itself, either during or after the conflict; "it will be answerable to international justice" he added. Macron also called for an international meeting on Syria, in the region if possible. In a telephone call with Russian President Vladimir Putin last week, Macron said he was "worried about indications suggesting the possible use of chlorine on several occasions against the civilian population in Syria these last few weeks". Russia has intervened alongside Syrian regime forces in the seven-year civil war and Putin is seen as the foreign leader with the most influence over Syrian President Bashar al-Assad. Receiving Putin at Versailles in May 2017, Macron had declared that France would respond immediately to any use of chemical weapons in Syria. "A very clear red line exists on our side: the use of chemical weapons by anyone," Macron said, promising "retaliation and an immediate response from France". According to Washington, at least six chlorine attacks have been reported since early January in rebel areas, with dozens injured. The Syrian regime in late January denied carrying out chemical weapons attacks and its ally Moscow denounced the charges as a "propaganda campaign", stressing that the perpetrators had not been identified. While France, like the United States, suspects the regime, it says it does not yet have concrete evidence on the nature and origin of the attacks. On Wednesday last week, Foreign Minister Jean-Yves Le Drian said "all indications" suggest that Assads forces were using chlorine weapons in the civil war against rebel forces, but being cautious said "we havent completely documented this". But Defense Minister Florence Parly was more reserved on Friday when asked if Damascus had crossed the "red line". "We have some indications of the use of chlorine, but we do not have absolute confirmation, so it is this confirmation work that we are doing with others because obviously we have to establish the facts," she said. Damascus has repeatedly been accused of using chemical weapons, with the United Nations among those blaming government forces for an April 2017 sarin gas attack on the opposition-held village of Khan Sheikhun that left scores dead. Last week was one of the bloodiest in the Syrian conflict as regime forces, who are backed by Russia and Iran, bombarded two of the last major rebel areas of Syria - Eastern Ghouta near Damascus and the northwestern province of Idlib. Syria signed the international treaty banning chemical weapons and allowed monitors to destroy its poison gas arsenal after an agreement reached in 2013 to avert US retaliation for what Washington said was a nerve gas attack near Damascus that killed more than 1,000 people. In recent weeks, rescue workers, aid groups and the United States have accused Syria of repeatedly using chlorine gas, which it possesses legally for uses such as water purification, as a chemical weapon against civilians in Ghouta and Idlib. France, a permanent member of the UN Security Council, has struggled to wield influence on Syria. Critics who accuse Macron of inaction say he has not given a clear definition of whether use of chlorine would for him constitute a chemical attack. On Tuesday, the vice president of the Syria Civil Defense, or “White Helmets”, volunteer force said France should stop talking and take real action.