“We've talked for a long time about approaching a constitutional crisis.

We are now in it.” House Judiciary committee chairman Jerrold Nadler on Wednesday declared the United States is officially in a constitutional crisis, after the panel he leads approved a measure to hold U.S. Attorney General William Barr in contempt for refusing to hand over an unredacted copy of the Mueller report.

“This is whether we can put limits on the president - any president - and the executive branch, and hold the president - any president - accountable." The vote comes after President Donald Trump asserted executive privilege to block the full Mueller report and its underlying evidence from being released.

The fight between the two branches government has only just begun, says Reuters Legal Correspondent Jan Wolfe.

The House panel voted along party lines on the contempt resolution, after Barr defied a subpoena to hand over Mueller’s full unredacted report.

The White House blasted Nadler's actions as a "blatant abuse of power," saying he had left Trump "no other option" than to invoke executive privilege.

That view was shared by Republicans on the panel.

House Speaker Nancy Pelosi – in an interview with the Washington Post Wednesday – said Trump isn’t doing himself any favors, as the White House stonewalled numerous investigations by House Democrats in the wake of Mueller's report, which said Trump had repeatedly tried to impede the nearly 2-year probe.

"Every single day the president is making the case.

He's becoming self-impeachable." The Trump administration also told former White House counsel Donald McGahn not to comply with a subpoena seeking documents, after Mueller’s report said Trump had pushed McGahn to have Mueller fired.

Trump has denied any wrongdoing and vowed to fight all congressional subpoenas.