Journalist Bob Woodward's new book claims former President Donald Trump may have held up to seven private phone calls with Russian President Vladimir Putin since leaving office. This revelation refocuses attention on Trump's relationship with Putin, raising concerns given past investigations into Russia's interference in the 2016 election and Trump's recent statements on U.S. aid to Ukraine. Trump's campaign has denied these calls, with the Kremlin also rejecting the claim. Trump's alleged private calls with Putin after leaving office could potentially violate the Logan Act, a law prohibiting unauthorized private citizens from negotiating with foreign governments on behalf of the U.S.