Steve Bannon was sent a subpoena by Robert Mueller as part of his investigation into potential collusion between the Trump campaign and the Russian government during the 2016 presidential election. The New York Times reports that Bannon became the first person in Trump's inner circle to be subpoenaed to testify before a grand jury in the on-going investigation.
The report says the subpoena could be a negotiating tactic and that Bannon may be able to avoid testifying in front of a grand jury if he agrees to "be questioned by investigators in the less formal setting of the special counsel’s offices."
Mueller issued the subpoena after explosive quotes attributed to Bannon were released ahead of the publication of Fire and Fury: Inside the Trump White House. In the book, Bannon described a June 2016 meeting between Donald Trump Jr., Paul Manafort, Jared Kushner, and Russian attorney Natalia Veselnitskaya as "treasonous" and "unpatriotic." That meeting has been a major focus of the Mueller investigation into collusion between the Kremlin and the Trump campaign.
News of the subpoena comes as Bannon was on Capitol Hill testifying behind closed doors in front of the House Intelligence Committee. Bannon was expected to testify about his role during the Trump campaign and not about his time working in the White House.