But most aren't yet criticizing him either.

President Donald Trump might have leaked classified information to the Russian government, the Washington Post reported Monday, and for perhaps the first time in his scandal-soaked presidency, Republicans on Capitol Hill did not immediately rise to his defense.

On Tuesday morning, Senate Majority Leader Mitch McConnell had only commented on how the “drama” from this report would slow down the Republican conference’s packed legislative agenda on Capitol Hill.

When the news broke, no GOP leaders in the House or Senate had released statements supporting Trump after the disclosure, which was confirmed by multiple media outlets. House Speaker Paul Ryan expressed hope, through a spokesperson, for a “full explanation” from the administration as to what had happened.

Other Republicans were cautious — but notably not rushing to support Trump.

Sen. John Thune, the chair of the Republican conference, told reporters Monday night, “I would be concerned anytime we're discussing sensitive subjects with the Russians, yes.” The “concern” only became more aggressive on Tuesday.

“There are lots of risks. If they say it was classified, then it was public knowledge; then you hurt the national security of the United States. That’s why you classify it,” Sen. John McCain (R-AZ), who has been a critic of Trump’s relationship with Russia, said.

In a statement he reiterated that the report was “deeply disturbing”:

The reports that the president shared sensitive intelligence with Russian officials are deeply disturbing. Reports that this information was provided by a U.S. ally and shared without its knowledge sends a troubling signal to America’s allies and partners around the world and may impair their willingness to share intelligence with us in the future. Regrettably, the time President Trump spent sharing sensitive information with the Russians was time he did not spend focusing on Russia’s aggressive behavior, including its interference in American and European elections, its illegal invasion of Ukraine and annexation of Crimea, its other destabilizing activities across Europe, and the slaughter of innocent civilians and targeting of hospitals in Syria.

No action from Republicans, just more concern

Sen. Susan Collins (R-ME), a member of the Senate Intelligence Committee, left her health care working group Monday night looking for more information. “I can tell you as a member of the Intelligence Committee, we had not been told that this had happened by this administration,” she said. “It’s very serious, I want to find out what the facts are.”

GOP leaders shared that “looking for answers” sentiment in the early reactions to the news. “We have no way to know what was said, but protecting our nation's secrets is paramount,” Doug Andres, a spokesperson for Speaker Ryan, said. “The speaker hopes for a full explanation of the facts from the administration."

Trump’s strongest initial defense appeared to come from Rep. Jason Chaffetz, the Republican chair of the House Oversight Committee, who has been reluctant to investigate Trump. He told the Salt Lake Tribune’s Thomas Burr that “of course” he still trusts Trump with classified information, and added that the House Intelligence Committee should review the validity of the Post’s report.

The fiercest critique came from Sen. Bob Corker of Tennessee, the chair of the Senate Foreign Relations Committee. "To compromise a source is something that you just don't do," Corker told reporters. "That's why we keep the information that we get from intelligence sources so close, is to prevent that from happening."

While Republicans keep quiet, Democrats are outraged

Unsurprisingly, Democrats were quicker to jump to outrage. The premise of Trump revealing classified information was jarring enough — especially given how strongly Trump and the Republican Party attacked Hillary Clinton for allegedly doing the same.

Rep. Eliot L. Engel of New York, the Democratic ranking member of the House Committee on Foreign Affairs, said he was “shocked,” in a statement:

I am shocked by reports that President Trump revealed highly classified information to Russian diplomats last week. This certainly raises questions about whether the President recognizes the serious implications of disclosing such sensitive information to an adversary. I will be meeting later this week with National Security Advisor McMaster in a classified session, and will seek answers about what was revealed and how it could damage American national security. It’s time for Congress to come together in a bipartisan way, establish an independent commission to investigate, and get to the truth.

Sen. Mark Warner of Virginia, the Democratic vice chair of the Senate Intelligence Committee, had similarly chiding words.

“If true, this is a slap in the face to the intel community,” he tweeted. “Risking sources and methods is inexcusable, particularly with the Russians.”

Like Republicans, Minority Leader Rep. Nancy Pelosi called for a briefing on the report, expressing just how “dangerous” an idea it is.

“If the news reports are true, President Trump has compromised a key source of intelligence collection against ISIS and jeopardized the security of the American people,” Pelosi said in a statement. “Even if President Trump unwittingly blew a highly classified code-word source to the Russians, that would be dangerous enough. If the President outed a highly classified code-word source intentionally, that would be even more dangerous.”

Lawmakers on both sides of the aisle expect a briefing in the coming days. Sen. Chris Murphy of Connecticut, a Democratic member of the Senate Foreign Relations Committee, said he is waiting for Republicans to see this as a red flag to prioritize investigations into Trump’s reported ties with Russia.

“I don’t know when it will be enough for Republicans to understand that we need to get to the bottom of the connection between the president of the United States and the Russian government,” he told reporters.