Iran is ready to work with the United States and its allies to stop Islamic State militants, but would like more flexibility on Iran’s uranium enrichment program in exchange, senior Iranian officials told Reuters. The comments from the officials, who asked not to be named, highlight how difficult it may be for the Western powers to keep the nuclear negotiations separate from other regional conflicts. Iran wields influence in the Syrian civil war and on the Iraqi government, which is fighting the advance of Islamic State fighters. Iran has sent mixed signals about its willingness to cooperate on defeating Islamic State (IS), a hard-line Sunni Islamist group that has seized large swaths of territory across Syria and Iraq and is blamed for a wave of sectarian violence, beheadings and massacres of civilians. Iran’s Supreme Leader Ayatollah Ali Khamenei said recently that he vetoed a U.S. […]