Russian president Vladimir Putin and his French counterpart Emmanuel Macron have discussed cooperating more closely to resolve the Syrian crisis, as France tries to smooth ties with Russia and move beyond years of tension over Syria and Ukraine.

Mr Macron spoke to Mr Putin by phone as the French leader prepares to attend the St Petersburg Economic Forum in May, where the two presidents will meet.

The Kremlin said Mr Putin and Mr Macron underlined the need for closer co-operation on Syria.

Mr Macron’s office said he pushed for more robust Syrian peace talks — notably after a Russia-sponsored effort last month boycotted by the Syrian opposition.

The French president also pressed Mr Putin to stop “intolerable degradation of the humanitarian situation” in regions of Syria that were pummelled by Syrian and Russian air strikes in recent days.

The presidents discussed another sore point in relations: the conflict in Ukraine. They stressed the need to enforce the 2015 Minsk peace agreement which was sponsored by France and Germany.

Mr Putin and Mr Macron also hailed a potentially problematic project to encourage contacts among Russian and French citizens. Called the Trianon Dialogue, the initiative appears aimed at minimising European sanctions against Russia for its support of separatists in eastern Ukraine.

The French-Russian project was set up to encourage interactions through joint theatre productions, school trips, sister city agreements and real estate investments.

However, geopolitical tensions threaten to complicate the effort.

Among the Russians overseeing the Trianon Dialogue are magnate Gennady Timchenko, a longtime associate of Putin’s, and former railways chief Vladimir Yakunin — both targets of US sanctions over Russia’s actions in Ukraine. A former ambassador who is an outspoken supporter of Russia’s bombings of Syria and annexation of Crimea is also involved.

An official in Mr Macron’s office acknowledged that “we may run into difficulties” in juggling the project’s open-arms mission with current East-West tensions. The official said the French side would remain “vigilant” to prevent Mr Putin’s administration from using the event for political ends.

Mr Macron has remained publicly committed to the European Union’s sanctions on Russia, but the Trianon Dialogue could be seen as undermining them.

Insiders said he pushed for the project “to encourage Franco-Russian economic relations” despite curbs on trade prompted by the sanctions and a Russian embargo.

The French members of the project’s board all hail from outside politics. They include an astronaut, a ballet star, the director of the Versailles Chateau and the CEOs of oil giant Total and car-sharing company Blablacar.