Iran has taken steps in recent days to file what it claims are 18 instances in which America violated the landmark nuclear agreement, a move that could set the stage for Tehran to abandon the deal and lay blame on the Trump administration, according to regional reports and sources familiar with the matter. On the heels of an effort by the Trump administration to tighten the nuclear accord while still upholding U.S. commitments under it, the Iranian Foreign Ministry has submitted to European Union leaders a plethora of information recounting what it claims are 18 separate violations of the deal...