Now the New York Times is reporting Flynn's legal team has ended an agreement to share information about the Russian Federation probe, led by special counsel Robert Mueller, with lawyers representing Donald Trump and the White House. Sharing of information between a cooperative witness and a person or institution still under investigation is considered unethical.
Flynn's lawyers notified Trump's lawyers of the decision in the past few days, according to four people involved in the case who spoke to the newspaper.
The grand jury convened for the investigation and will soon have a chance to question individuals witnesses about Kian's activities, NBC News reported.
If true and Flynn is cooperating with Mueller, it could result in a much more scrutinized look into the Trump campaign.
Mueller is now conducting a special investigation to look into Russian interference in the 2016 election and any potential ties between the Trump campaign and Russia.More news: Charlie Rose fired after multiple sexual harassment claims
More news: IPhone Factory Reportedly Forced Students to Work 11-Hour Days
More news: Consumer group warns of 'Trouble in Toyland'
Mueller's rapidly progressing probe has already landed indictments against former Trump campaign chairman Paul Manafort and his deputy Rick Gates.
Among the interactions that Mr. Mueller is investigating is a private meeting that Mr. Flynn had with the Russian ambassador and Jared Kushner, the president's son-in-law, during the presidential transition.
Flynn's company has garnered heavy scrutiny since it was revealed that it was paid $530,000 for lobbying on behalf of a firm called Inovo BV, owned by a Turkish-American businessman.
The Times' report Thursday comes just weeks after CNN reported Flynn was concerned about the potential legal exposure of his son, Michael Flynn Jr.in the investigation. Mueller could potentially use this to charge Flynn with making false statements - the same charge that former Trump campaign adviser George Papadopoulos pleaded guilty to last month.