Iranian Supreme Leader Ayatollah Ali Khamenei has backed the government's decision to increase gasoline prices.<br />'' <br />'' The country's state television reported Khamenei saying that those setting fire to public property during protests against the hikes are backed by counter-revolutionaries and the enemies of Iran.<br />'' <br />'' The Supreme Leader's comments came just days after a 50 per cent hike in gasoline prices sparked protests across the country.<br />'' <br />'' At least two people have been killed during the protests.<br />'' <br />'' Meanwhile, Iran's Interior Minister has warned that security officials will step up action against the protesters. <br />''