Moscow/Washington: Moscow and Washington have reconfirmed their efforts in trying to reach a peaceful solution in Syria, saying they aim to "redouble efforts" to accomplish a political settlement of the conflict. The joint statement by co-chairs of the International Syria Support Group, which was released on Monday recognized "the progress that has been made with respect to the cessation of hostilities," but also highlighted that there have been certain "difficulties... in several areas of the country," RT online reported. To increase efforts toward peace, Russia and US have been "using influence" with parties on the ground, aiming to "press them to abide" by the cessation of hostilities agreement that went into effect on February. Both Moscow and Washington have also called on regional forces to "refrain from disproportionate responses to provocations and demonstrate restraint." Demanding that "indiscriminate attacks on civilians" are ceased by all parties, Russia has also said that it would work with the Syrian authorities in order to "minimize aviation operations over areas that are predominantly inhabited by civilians or parties to the cessation." Washington meanwhile will work with "regional allies" by assisting them in prevention of any "flow of fighters, weapons or financial support to terrorist organizations across their borders." The ISSG co-chairs said that further efforts should be put in preventing any "material or financial support" to Islamic State, Al-Nusra and other groups designated as terrorist organizations by the UN Security Council. Speaking to US Secretary of State John Kerry on the phone on Monday, Russian FM Sergey Lavrov said that measures must be taken to stop "extremists" in Syria being supplied via Turkish territory. Saying that the joint efforts "have brought about a significant decrease in violence" in a number of Syrian regions, the statement added: "The Russian Federation and United States are determined to redouble efforts to reach a political settlement of the Syrian conflict consistent with UNSCR 2254 through the intra-Syrian negotiations in Geneva under UN auspices."