The Senate Intelligence Committee has sent letters requesting testimony from both former FBI Director James Comey and former deputy director Andrew McCabe, Chairman Richard Burr (R-N.C.) told reporters on Wednesday.

The requests are for testimony in both open and closed sessions, Burr said, and neither has yet responded.

Both officials have testified before the Senate Intel panel since President Trump took office - Comey in a blockbuster appearance shortly after his dismissal last spring and McCabe the following month.

The news of the request comes just days after the Justice Department inspector general (IG) released a deeply critical report documenting the bureau's handling of the Clinton email investigation, in which he criticized Comey's decisions in that probe as "insubordinate" and "extraordinary."

Earlier this spring, the IG also released a report on McCabe's conduct that concluded that the former official provided an unauthorized leak to the media and then misled investigators - and Comey - about the matter.

McCabe was dismissed by Attorney General Jeff Sessions in March after the FBI's Office of Professional Responsibility found that the 20-year veteran made an unauthorized disclosure to the news media and "lacked candor - including under oath - on multiple occasions."