Federal agents questioned Manafort in March 2013 and again in July 2014, newly filed court documents obtained by The Washington Post revealed.
The court filings were released by the office of Special Counsel Robert Mueller, who is currently investigating the Trump campaign's alleged ties to Russia.
The FBI gave Manafort copies of his previous FBI interviews.
Mueller is investigating allegations that Russia interfered in the 2016 US election and claims that Trump's campaign team colluded with Moscow to influence the outcome of the vote.
Russian officials have repeatedly denied allegations of interference, calling the accusations "absurd." Trump has also denied any collusion between himself and the Kremlin and has called Mueller's investigation a "witch hunt."