US Secretary of State John Kerry, French Foreign Minister Laurent Fabius — who cancelled a visit to Mongolia for the talks — and British Foreign Secretary William Hague will attend the working lunch, it said.
France said that the Syrian regime's announcement that it had joined a ban on chemical weapons was not enough and called for a binding UN Security Council resolution.
"The Syrian regime's announcements are certainly very useful but also certainly insufficient," French foreign ministry spokesman Philippe Lalliot said, as Washington and Moscow met in Geneva for talks on dismantling Syria's chemical arsenal.
Syrian President Bashar al-Assad confirmed for the first time that Syria planned to relinquish its chemical arms under a Russian plan aimed at averting US-led military action against his regime.
As a first step, Syria filed documents at the United Nations seeking to join the international convention banning chemical weapons.
But Lalliot said that for France — Washington's main backer in launching military strikes — that wasn't good enough.
"We cannot remain with only a statement of intent from the Syrian regime. It must make commitments and these must be fixed, controlled, verified and verifiable," he said.
"There needs to be a (UN Security Council) resolution, because by its very nature that's a binding text," Lalliot said. "Any other text within the Council is insufficient."