Iranian Supreme Leader Ayatollah Ali Khamenei said Sunday that the United States is a main cause of problems in the Middle East and not part of the solution.Speaking during a meeting with Iranian Foreign Minister Mohammad Javad Zarif and Iranian ambassadors, Khamenei said that "Iran's foreign policy has barred like a firm dam, the tyranny of hegemonies, mostly the US. They wish for change in these policies."Iran's top authority said elections should be held in Syria to end the civil war there and criticized foreign powers that arm and fund Syrian opposition fighters, state television reported on Sunday."The solution to the Syrian question is elections, and for this it is necessary to stop military and financial aid to the opposition," several state media outlets quoted Khamenei as saying. He added that US objectives in the Middle East were the opposite of Iran's and negotiating with Washington on regional issues was meaningless.