Moscow is awaiting a tripartite summit in Tehran next Friday to develop a Russian-Turkish-Iranian joint vision on a solution in Idlib, while Foreign Minister Sergei warned that Russia “could not indefinitely” tolerate the situation in the opposition-held Syrian province. Speaking to university students in Moscow on Monday, Lavrov said the Syrian regime, Russia’s ally, had every right to wipe out militants in northern Idlib, Interfax news agency reported. In a message addressed to Ankara, Lavrov stressed the need to separate the moderate opposition from terrorists. "We are now taking the most active effort, together with our Turkish colleagues, together with the Syrian government, and with the Iranians as participants in the Astana format, to split the armed normal opposition forces from the terrorists on the ground,” Lavrov said. Meanwhile, Iranian Foreign Minister Mohammad Javad Zarif arrived Monday on a surprise visit to Damascus, where he held talks with head of the Syrian regime Bashar Assad and his Foreign Minister Walid al-Moallem, who is just back from a visit to Moscow. His visit to Syria follows that of Iranian Defense Minister Amir Hatami last week. Zarif met Assad to discuss "issues on the agenda for the tripartite meeting," according to the Syrian presidencys account on the Telegram messaging app. Assads office also said Iran and Syria "had similar views on the different issues" to be discussed. On Sunday, informed Syrian sources told Asharq Al-Awsat that regime forces were awaiting presidential orders to kick off an offensive against Idlib. Assad has pledged to defeat the opposition in its last refuge in the northwestern province if the fighters do not surrender to government rule. Sources said Monday that differences between Russia and Turkey concerning the situation in Idlib have declined following talks held between the two sides in the past weeks. However, Russian media outlets said the gap has widened between Moscow and Tehran. A Russian expert wrote on the Svobodnaya Pressa website that “Tehran is no more in need of Moscow in Syria,” and that it was working on enhancing its own presence and interests there.