Special counsel Robert S. Mueller, who is overseeing the probe into Russia's alleged meddling in the 2016 presidential election, is interviewing senior intelligence officials to examine whether President Donald Trump attempted to obstruct justice.
According to a Washington Post report, the move to investigate President Trump's conduct marks a major turning point in the investigation, which until recently focused on whether there was any coordination between the Trump campaign and Moscow.
Investigators have also been looking for any evidence of possible financial crimes among Trump associates, the reported quoted officials, as saying.
Trump had received private assurances from then FBI director James B. Comey starting in January that he was not personally under investigation. Officials say that changed shortly after Comey's firing.
Daniel Coats, the current director of national intelligence, Mike Rogers, head of the National Security Agency, and Rogers's recently departed deputy, Richard Ledgett, agreed to be interviewed by Mueller's investigators as early as this week, said the report.