The Justice Department has withdrawn recent subpoenas in its investigation of former CIA Director John Brennan, opting instead to seek voluntary interviews with witnesses.

The inquiry, which centers on allegations that Brennan made false statements about the 2016 intelligence assessment on Russian election interference, is one of several probes targeting critics of President Donald Trump.

The decision came shortly after changes in the prosecution team, including the addition of Trump ally Joe diGenova.

Brennan, who led the CIA under President Barack Obama, denies any wrongdoing and calls the investigation politically motivated, the AP has reported.

Officials have not explained why the subpoenas were reversed, and the investigation is still ongoing.