President Donald Trump on Thursday said Republican Sen. Markwayne Mullin will replace Kristi Noem as Department of Homeland Security secretary.
Trump made the announcement on social media Thursday afternoon saying he was “pleased to announce that the Highly Respected United States Senator from the Great State of Oklahoma, Markwayne Mullin, will become the United States Secretary of Homeland Security (DHS), effective March 31, 2026.”
Sen. Markwayne Mullin speaks during a Senate Health, Education, Labor and Pensions Committee hearing on Capitol Hill on February 25, 2026 in Washington.
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“The current Secretary, Kristi Noem, who has served us well, and has had numerous and spectacular results (especially on the Border!), will be moving to be Special Envoy for The Shield of the Americas, our new Security Initiative in the Western Hemisphere we are announcing on Saturday in Doral, Florida. I thank Kristi for her service at ‘Homeland,'” Trump said in the post.
This marks the first Cabinet secretary that Trump has fired in his second term.
Shortly after Trump’s decision, Mullin told reporters that he was “excited” about leading DHS and “ready to get started.”
“My focus is to keep the homeland secure,” he said.
Sen. Markwayne Mullin tapped by U.S. President Donald Trump to replace U.S. Homeland Security Secretary Kristi Noem, speaks to members of the media as he departs the U.S. Capitol in Washington, March 5, 2026.
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Asked about replacing Noem, Mullin said she “is a friend” who was “tasked with a very difficult job.”
Asked by ABC News’ Senior Political Correspondent Rachel Scott what, if anything, Mullin could learn from Noem’s time leading the agency, he said that “there’s an opportunity to build off successes, and there’s also opportunities to build off things that maybe didn’t go quite as planned.”
Homeland Security Secretary Kristi Noem testifies during a House Committee on the Judiciary oversight hearing of the Department of Homeland Security on Capitol Hill, March 4, 2026, in Washington.
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In a social media post Thursday afternoon, Noem thanked Trump for the new appointment.
“In this new role, I will be able to build on the partnerships and national security expertise, I forged over the last 13 months as Secretary of Homeland Security,” Noem said.
The news that the Oklahoma senator would take over Noem’s job came after several sources told ABC News that Trump had called Republicans and top allies asking if he should fire her.
The president had privately expressed deep frustration over Noem’s testimony during the Senate Judiciary Committee hearing on Tuesday, those sources with direct knowledge of the conversations said.
The sources said the president was upset with a particular moment during the hearing when Republican Sen. John Kennedy questioned Noem about a taxpayer-funded $220 million ad campaign. Noem repeatedly suggested the president was aware of the campaign and signed off on it.
A senior administration officials tells ABC News that the president did not sign off on a $220 million ad campaign.
“Absolutely not,” the senior administration official said.
Kennedy told reporters Thursday that Trump even called him about it.
“I’m not going to speak for him. You folks know him. You can ask him yourselves, but his, I want to put it this way, his recollection and her recollection are different,” Kennedy said.
DHS Secreatary Kristi Noem speaks in Nashville, Tenn., on March 5, 2026.
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Tuesday’s hearing was just the latest in several incidents that have sparked concern among Trump administration officials and some Republicans on Capitol Hill, sources tell ABC News.
Just days ago, Noem and her top adviser Corey Lewandowski made the decision to temporarily suspend TSA Precheck amid the partial government shutdown — which later had to be reversed after the White House stepped in, according to sources.
Noem has faced criticism in recent weeks over her handling of Immigration and Customs Enforcement operations in Minneapolis after the killings of Renee Good and Alex Pretti by federal law enforcement. She was removed from leading operations in the state following the scrutiny, and Border Czar Tom Homan was sent in to take over.
During a Cabinet meeting in January, the president did not call on Noem to speak.
