Washington (CNN) National security adviser H.R. McMaster has resigned and will be replaced by former US ambassador and Fox News analyst John Bolton, President Donald Trump announced in a tweet on Thursday. "I am pleased to announce that, effective 4/9/18, @AmbJohnBolton will be my new National Security Advisor. "I am thankful to President Donald J. Trump for the opportunity to serve him and our nation as national security advisor. Trump's first national security adviser, Michael Flynn, resigned amid controversy over his contact with Russian officials within a month of taking the job.

Source: CNN March 22, 2018 22:37 UTC