Rex Tillerson’s already-shaky position within Donald Trump’s Cabinet is suddenly looking perilous. Simmering tensions between the president and his top diplomat spilled out into the open on Wednesday amid reports that the secretary of state had threatened to resign and called his boss a “moron” over the summer. Tillerson’s subsequent non-denial denial reportedly left Trump fuming and Chief of Staff John Kelly scrambling to contain the fallout, spurring a fresh wave of speculation that the long-rumored “Rexit” may be imminent.

Trump was livid when the “moron” story broke, according to NBC News, which first reported that Tillerson had vented about the president earlier this summer. With Trump on the warpath, Kelly reportedly canceled his plans to travel to Las Vegas with the president to clean up the mess, summoning Tillerson and Defense Secretary James Mattis to outline a response to the deluge of negative press coverage. By 11 a.m. on Thursday, Tillerson was behind a lectern in damage-control mode, declaring that he “had never considered leaving” his post and praising the president.

Still, Tillerson stopped short of outright denying that he had called the president a “moron,” ushering in a fresh news cycle. When Trump insisted that NBC News had made up the story, and that nobody sought “verification” from him, the network hit back. “Sir, we didn’t need to verify that he called you a moron, he did it behind your back,” MSNBC’s Stephanie Ruhle said on air, delivering another round of bad press and further enraging the president. On Friday morning, Axios cited insiders as saying the relationship is “broken beyond repair,” with Trump furious that Tillerson didn’t shut down the story.

Kelly is reportedly trying to stanch the bleeding, figuring that another major staff shake-up will only further destabilize the administration. But the relationship between the White House and Foggy Bottom is so toxic, sources told Jonathan Swan, that there may be no coming back. Vice President Mike Pence was said to be particularly irked that R.C. Hammond, Tillerson’s communications adviser and top spokesperson, had told NBC News that Pence once raised questions about whether Nikki Haley—the United States ambassador to the United Nations and a potential successor at State—was an asset to the administration. The vice president was “very annoyed anyone would misrepresent anything he said, particularly in private meetings,” according to one White House official who spoke with NBC News.

Hammond apologized on Twitter, saying he “spoke out of line about conversations I wasn’t privy to.” And on Friday, the Pentagon announced that the State Department had approved part of an arms deal with Saudi Arabia, ending an intra-agency dispute that had complicated relations between Tillerson and the White House. Still, the damage has been done. Speculation that Tillerson’s days are numbered grew over the summer, when the former ExxonMobil C.E.O. distanced himself from Trump’s comments on Charlottesville, telling Fox News that “the president speaks for himself.” He repeatedly broke with the White House over a number of key foreign-policy issues, including on Saudi Arabia and North Korea.

With few allies on Capitol Hill and fewer friends within the State Department, which he has been working to downsize, there aren’t many people in Washington left to speak on Tillerson’s behalf. For months, Haley has been viewed as Tillerson’s heir apparent. Now, according to Axios, Trump allies and advisers are also floating C.I.A. Director Mike Pompeo as a possibility.

The best argument for Pompeo would be his potential to heal the rift between State and the White House. One top career foreign service officer who left the State Department earlier this year told me that Pompeo’s strong relationship with the president would be “a very good thing” for the agency, and that his involvement with the National Security Council as C.I.A. chief would ensure he wouldn’t “have a learning curve in terms of the issues or a relationship with [his] boss.”