Federal investigators are reportedly probing Donald Trump’s finances, and his staff is nervously awaiting the president’s all-but-inevitable, cable news-fueled response.

Justice Department special counsel Robert Mueller is looking into Trump and his family’s personal financial matters, CNN reported on Thursday. He has also escalated the investigation with subpoenas, a new federal grand jury, and additional staff that together indicates the probe is intensifying.

As news of that expansion trickled out Trump was on the way to West Virginia for a campaign rally. There he stayed on message—only briefly railing on Democrats, repeating a familiar White House line that the investigation is part of a “totally made up Russia story” concocted by Hillary Clinton’s allies.

“There were no Russians in our campaign. There never were,” Trump said, misstating the nature of the allegations against him. The entire premise of the investigation, he insisted, is a “total fabrication.”

Left unsaid was what, if anything, he plans to do about it.

Inside the White House, it’s not just the potential legal jeopardy that has officials concerned; it’s how President Trump might react to news that his and his family’s finances are under investigation—and the political and legal consequences that could ensue from a Trump backlash against the news.

“Outside counsel is handling all that so legal developments aren’t really front and center,” one senior Trump official told The Daily Beast of the expanded scope of the investigation, and news that Mueller has impaneled a grand jury in Washington. The Daily Beast independently confirmed that development on Thursday, a development that signals the investigation is picking up steam.

“The worry is what the president does now,” the official said. “Whether he does something that’s gonna make everything else even more difficult.”

The official alluded to Trump’s interview with the New York Times last month, in which he agreed that Mueller would cross a “red line” by expanding his investigation from alleged Russian election meddling into the Trump family’s finances. Jay Sekulow, a member of the president’s outside legal team, reiterated that position to CNN on Thursday. “Any inquiry from the special counsel that goes beyond the mandate specified in the appointment we would object to,” he said.

Mueller and his team are now firmly on the wrong side of that “red line,” and Trump staffers are worried at the prospect that he could follow through on his threat—or at the very least dig the White House deeper into a legal and public relations hole with ill-considered tweets or public statements that have become his hallmark.

“Just keep him off the Twitter and on the teleprompter,” the White House official said. Officials spoke on the condition of anonymity because they weren’t cleared to discuss these sensitive matters.

Trump can’t technically fire Mueller, but he can direct deputy attorney general Rod Rosenstein to do so. The move would set off a political firestorm, and likely draw criticism from both sides of the political aisle.

Two bipartisan Senate bills are already making their way through that chamber that would remove the president’s authority to oust the special counsel. Sen. Chris Coons, a Delaware Democrat and a sponsor of one those bills, raised the possibility that Trump might try to do so while the Senate is on its August recess.

The president “would be taking a risk if he assumed that he could act because the Senate was fully in recess,” Coons told reporters on Thursday. Senators could return to Washington over the recess to block him from firing Mueller, who is extremely popular on Capitol Hill, Coons said. Republicans and Democrats have warned Trump in recent weeks that it would be politically toxic if moves to remove the special counsel.

Even internally, Trump could face renewed pushback against any move on Mueller from his newly minted chief of staff. Two White House officials tell The Daily Beast that retired Marine Corps general John Kelly, who took over for ousted chief of staff Reince Priebus, would strenuously oppose the president if he tried to remove Mueller.

“I can’t imagine he’d sit idly and watch that happen,” one of the officials said, though neither specified what action he might take if Trump went that route.

For months, White House advisers have been urging the president—who has no qualms venting about Mueller and other top law-enforcement officials publicly—not to order the firing of Mueller, as aides generally recognize the “apocalyptic shitstorm,” as one White House adviser put it, that would result.

“[Trump] has gone up to the line of and flirted with the idea of firing [officials], including Sessions,” the Trump adviser said. “But we’re not at code red at all yet.”

Nevertheless, legal experts say the president has a history of digging himself deeper into a legal hole as new developments in the Russia investigation emerge. “Trump and his team seem incapable, as a matter of character, to react to [news of a new grand jury] in a prudent way or follow good advice or do the things you have to do to survive it,” Ken White, a former federal prosecutor who now practices criminal defense, told The Daily Beast.

“People react really stupidly to these proceedings all the time,” White explained. “They convince other people to lie for them, they destroy documents, they come up with lies they’re going to tell themselves, they do all sorts of idiotic things—not realizing part of a fed prosecutor’s point is often to drive them to do that.”

Multiple White House sources emphasized that, though some of this Russia-related news from Thursday isn’t entirely new, several major stories breaking in the span of one afternoon ups the chances of Trump-Russia investigation news playing wall-to-wall on the news—thus greatly increasingly the chances the president will notice the coverage, become distracted by it, grow infuriated by it, and lash out.

According to several Trump confidants, the president continues to regularly slip into casual, unrelated, and private conversation that he is “not under investigation”—a habit and verbal tick since at least the early summer—instead blaming bad PR, “phony” and “fake” stories, and “witch hunts” for his woes.

And Trump and his team are sticking to their story, even as the revelations pile up.

In response to the news Mueller was seating a grand jury in DC, White House press secretary Sarah Huckabee Sanders sent out a statement underscoring President Trump’s position, and the official White House line, that “former FBI director Jim Comey said three times the president is not under investigation and we have no reason to believe that has changed.”

For a young administration that is now used to experiencing fast, unexpected clips of politically inconvenient and legally complicating news, the past two weeks have been particularly chaotic for Team Trump. However, not every Trump ally is feeling the pressure this week.

Multiple senior members of Trump’s campaign who lost out on top slots in the Trump White House, told The Daily Beast Thursday evening that they could all only marvel at how lucky they were to not work in the administration.

One bluntly summed it up that they were glad they “do not have to deal with this shit."

— Additional reporting by Andrew Desiderio