State Dept Resignation
Richard Johnson,
a career civil servant who served as acting assistant coordinator in State’s Office of Iran Nuclear Implementation, had been involved in talks with countries that sought to salvage the deal in recent weeks, including Britain, France, and Germany — an effort that ultimately failed.
https://foreignpolicy.com/2018/05/11/top-state-department-nuclear-expert-announces-resignation-in-wake-of-trump-iran-deal-exit/
https://www.voanews.com/a/report-top-nonproliferation-expert-resigns-from-state-department-/4390450.html