Democrats in the US House of Representatives are about to vote on whether to hold Attorney General William Barr in contempt of Congress.
A BBC report says t he judiciary committee initiated the proceedings when Mr Barr refused to submit an unredacted version of Special Counsel Robert Mueller’s report.
President Donald Trump has hit back by asserting executive privilege over the report, shielding it from public view.
The White House accused Democrats of a “blatant abuse of power”.
But House judiciary chairman Jerrold Nadler said the Trump administration’s refusal to provide the full Mueller report to Congress amounts to a “constitutional crisis”.
The New York Democrat said his party had “no choice” but to move forward with the contempt vote, “otherwise, we have a monarchy”.