The use of chemical weapons in Syria is a red line for France and would result in reprisals, Emmanuel Macron said on Monday during his first meeting as president of France with his Russian counterpart Vladimir Putin.

“Any use of chemical weapons would results in reprisals and an immediate riposte, at least where France is concerned,” Macron said at a joint news conference with Putin in which he added that his aim was the fight against terrorism in the country. He said he wanted to work with Putin to that end.

The two countries back different sides in the Syrian conflict, with Putin behind regime head Bashar al-Assad and Macron part of a western coalition that supports rebel groups and has accused Assad of using chemical weapons in the past.

Macron said he had a frank exchange of views with Putin, and that the two had aired their disagreements on a number of subjects.

For his part, Putin said sanctions against Russia will not help stabilize east Ukraine. He also voiced the possibility for improving interaction with France on Syria.

Addressing forces present in Syria, Putin added that Russia has no details on how independent France is from the United States on operations in the war-torn country.

Towards the end of the meeting Macron said that reopening the French embassy in Syria is not a priority at the moment.