President Obama on Friday directed his diplomats to use “creative negotiations” to bridge a sharp divide with Iran over the fate of sanctions if it agrees to curb its nuclear program , signaling flexibility in hopes of keeping a tentative agreement from unraveling. Iranian leaders have insisted in recent days that the punishing sanctions be lifted as soon as a written accord is signed, a position that the country’s foreign minister reinforced on Friday. Mr. Obama did not repeat past American assertions that sanctions […]