Just a month after House Speaker Nancy Pelosi unequivocally stated her opposition to impeachment proceedings against President Trump, the Robert Mueller report has reignited the debate inside her caucus.

“Mueller’s report is clear in pointing to Congress’ responsibility in investigating obstruction of justice by the President,” Rep. Alexandria Ocasio-Cortez, D-N.Y., tweeted, announcing she’ll sign onto Rep. Rashida Tlaib’s, D-Mich., resolution urging the House Judiciary Committee to probe whether Trump committed impeachment-level offenses.

AOC SAYS SHE'LL SIGN IMPEACHMENT RESOLUTION

The sprawling and detailed Mueller report released Thursday, while effectively clearing the president and his associates on the Russia collusion charge central to the probe, outlined a series of Trump actions that were investigated as part of the obstruction-of-justice inquiry. Mueller did not reach a determination on that issue, but provided a cornucopia of dramatic anecdotes showing the president trying to curtail the special counsel investigation.

Among them, the report said he directed then-White House Counsel Don McGahn in June 2017 to tell the acting attorney general that Mueller “must be removed.” McGahn refused.

Trump himself maintained he had broad authority, as his allies dismissed suggestions any of this amounted to obstruction of justice.

“I had the right to end the whole Witch Hunt if I wanted. I could have fired everyone, including Mueller, if I wanted. I chose not to. I had the RIGHT to use Executive Privilege. I didn’t!” Trump tweeted late Thursday.

But a key passage in the report also was seen as a signal to Congress that lawmakers could take up the issue next, even though Attorney General Bill Barr and Deputy Attorney General Rod Rosenstein determined there was no obstruction case.

The report said: “Under applicable Supreme Court precedent, the Constitution does not categorically and permanently immunize a President for obstructing justice through the use of his Article II powers. The separation-of-powers doctrine authorizes Congress to protect official proceedings, including those of courts and grand juries, from corrupt, obstructive acts regardless of their source. … The conclusion that Congress may apply the obstruction laws to the President's corrupt exercise of the powers of office accords with our constitutional system of checks and balances and the principle that no person is above the law.”

The report also stated: "If we had confidence after a thorough investigation of the facts that the President clearly did not commit obstruction of justice, we would so state. However, we are unable to reach that judgment.”

Trump attorney Rudy Giuliani, speaking Friday on “Fox & Friends,” dismissed that line: “He doesn’t have to prove his innocence … when can you prove a negative?”

But while the Mueller report marked the end of the two-year probe, it was seen as a starting point for some congressional Democrats eager to take up the obstruction issue. The big question is whether senior Democrats long nervous about calls for impeachment could at some point go along with the push – even if it risks a political backlash going into 2020.

PELOSI ANNOUNCES OPPOSITION TO TRUMP IMPEACHMENT

House Judiciary Committee Chairman Jerry Nadler, D-N.Y., did not rule out impeachment proceedings on Thursday.

In a written statement responding to the report, Nadler said: “The Special Counsel made clear that he did not exonerate the President. The responsibility now falls to Congress to hold the President accountable for his actions.”

Rep. Adam Schiff, the chairman of the Intelligence Committee, said the acts described in the report "whether they are criminal or not, are deeply alarming in the president of the United States. And it's clear that special counsel Mueller wanted the Congress to consider the repercussions and the consequences."

Schiff, a California Democrat, said, "If the special counsel, as he made clear, had found evidence exonerating the president, he would have said so. He did not. He left that issue to the Congress of the United States."

Pelosi’s view will be key. She said in an interview last month she’s opposed to impeachment, calling the process “divisive” and adding, “He’s just not worth it."

In the wake of the report, she wrote in a letter to colleagues that the caucus has scheduled a conference call for Monday to discuss next steps, while saying the Mueller report “appears to directly undercut” Barr’s conclusion that Trump did not obstruct justice.

“Congress will not be silent,” she vowed.

Republicans sought to portray Democrats as unwilling to let go of the idea that Trump colluded with Russia to swing the election. "What you're seeing is unprecedented desperation from the left," tweeted Rep. Mark Meadows, R-N.C., a top Trump ally. "There was no collusion. It's over."

Fox News’ Jake Gibson and Chad Pergram and The Associated Press contributed to this report.