French Foreign Minister Laurent Fabius and US Secretary-of-State John Kerry will hold a telephone conversation later Friday to discuss the recent developments with the Syrian crisis and other issues, Foreign Ministry sources said. Foreign Ministry spokesman Philippe Lalliot said the two officials were to talk during the day but that the time was \"moveable\" in light of programmes. Syria will be the focus of the conversation as two chief diplomats prepare briefs for their respective Presidents, who are to meet next week. President Barack Obama and President Francois Hollande will meet at next week\'s G8 Summit being held in Northern Ireland under British chairmanship. Several sideline meetings are expected at the gathering of the world\'s most powerful nations. As Russia will also be attending, the G8 will be an opportunity to talks with the Russians about Syria and the difficult preparations for a peace conference that is illusively being fixed now for July after being delayed from June. Lalliot said that Kerry and Fabius would particularly be discussing the way forward now that the US had corroborated French evidence and scientific tests that the Damascus regime has used chemical weapons in the conflict, particularly Sarin gas. France said ten days ago that it has concluded use of this toxic nerve agent by forces loyal to Bashar Al-Assad and now the US has concluded similar findings. \"Not only do we have certainty that chemical weapons were used - Sarin gas to be precise - by the Syrian regime against the opposition, but we were the first State to announce this publicly,\" Lalliot declared. He added that France immediately agreed to share its information and findings with its \"closest partners, starting with the Americans and the commission mandated by the UN Secretary-General.\" \"What\'s news today is the announcement made last night by the Americans...who confirm in turn...the use of Sarin gas by the Syrian regime,\" the official noted. He said the use of chemical weapons by the regime has now been \"scientifically proven\" but he remarked that the UN mission to do on-site inspections in Syria and report to the Secretary-General must be allowed to do its job. He said this was even more important given the findings by France and the US. The UN mission from the Organisation for the Prevention of Chemical Weapons (OPCW) has not been allowed into Syria despite initial calls for inspections by Damascus. Sarin gas has been used \"locally and repeatedly\" and this was concluded by Paris and Washington, the spokesman indicated.