US Defense Secretary James Mattis warned the Syrian regime on Friday against launching any attacks against the “Syrian Democratic Forces”, which have liberated the city of Raqqa from ISIS terrorist group. In a news conference at the Pentagon, Mattis said that there was currently a “demarcation line” between areas controlled by the US-led coalition and those controlled by Syria and its Russian allies in western Syria. “We have said that we would operate on one side and the Russians on the other,” Mattis stated. “And we are still taking (ISIS) down. Nothing has changed.” “It’s a mistake” to cross that line, he stressed. The Kremlin announced on Friday that Russian President Vladimir Putin signed a deal on the expansion of the Russian naval facility in the Syrian port city of Tartus. Franz Klintsevich, vice-president of the upper house of Russian parliament’s defense and security committee, accused the US-led coalition of transferring ISIS leaders from Deir Ezzor by helicopters to the Hassakah countryside, stressing the presence of close cooperation between the coalition and the terrorists. Meanwhile, the Syrian Observatory for Human Rights (SOHR) reported that buses carrying fighters of “Hayyaat Tahrir Al-Sham” and their families have headed from Beit Jinn area towards Idlib Province in the Syrian north and Daraa Province in the south. SOHR explained that four buses headed towards Idlib carrying about 100 fighters of “Hayyaat Tahrir Al-Sham” and their families, while 6 buses have departed carrying fighters of the factions and their families, along with civilians who refused the agreement with the factions of Hayyaat Tahrir al-Sham and the regime forces, towards Daraa. Hezbollah’s “war media” said that the buses carrying the militants of Beit Jann and their families left the assembly center in the southwestern Damascus countryside towards the city of Idlib, “as stipulated in the agreement reached between the Syrian army and the armed groups in the region.”