(CNN) Deputy Attorney General Rod Rosenstein told special counsel Robert Mueller in a classified August 2, 2017, memo that he should investigate allegations that President Donald Trump's former campaign chairman Paul Manafort was "colluding with Russian government officials" to interfere in the 2016 presidential election.

Mueller was also empowered by Rosenstein to investigate Manafort's payments from Ukrainian politicians, a cornerstone of the Trump adviser's decades-long lobbying career that has resulted in several financial criminal charges so far.