WASHINGTON (Reuters) - U.S. President Donald Trump’s White House prevented a former aide from answering more than 200 questions posed by Democrats in Congress who are investigating whether Trump interfered with Special Counsel Robert Mueller’s Russia probe, according to a transcript released on Monday.

The White House is pictured shortly after sunrise in Washington, August 1, 2007. REUTERS/Jason Reed

Former White House lawyer Annie Donaldson repeatedly told the House of Representatives Judiciary Committee that the White House had directed her not to answer questions about various incidents described in Mueller’s 488-page report.

“The White House has directed that I not respond to this question because of the constitutionally-based Executive Branch confidentiality interests that are implicated,” she said - a total of 212 times.

The Democratic-controlled committee called those confidentiality concerns a “sham principle” that has not been recognized as legitimate in court.

The White House did not immediately respond to a request for comment.

Donaldson’s silence meant little light was shed on incidents outlined in Mueller’s 488-page report, including an alleged effort by Trump to have Donaldson’s boss, former White House Counsel Don McGahn, remove Mueller from the investigation.

White House lawyers similarly prevented former communications aide Hope Hicks from answering more than 150 committee questions during an interview last month.

Donaldson, who served as McGahn’s former chief of staff, was present for several episodes described in the Mueller report that House Democrats are looking into as they weigh possible impeachment proceedings against Trump.

The report, released by Mueller in redacted form in mid-April, cites Donaldson as a source of information on Trump’s role in the departures of former national security adviser Michael Flynn and former FBI Director James Comey.

It also recounts Trump’s efforts to persuade former Attorney General Jeff Sessions to redirect the Russia investigation away from Trump’s 2016 presidential campaign.

Mueller’s investigation found that Russia had interfered in the 2016 election on Trump’s behalf, but concluded that Trump’s campaign had not illegally conspired with the Kremlin. It also outlined several instances where Trump tried to interfere with the investigation, but reached no conclusion as to whether that amounted to obstruction of justice.

Donaldson confirmed the accuracy of some of those incidents. But she declined to explain her handwritten notes that appeared in Mueller’s report, citing instructions from the White House.

Donaldson, who is pregnant, provided written answers under an agreement with congressional investigators because of the difficulty she would have traveling from her home in Alabama. She has agreed to testify in person after Nov. 1 if necessary.