US Navy Secretary John Phelan is leaving his post with immediate effect, the Pentagon announced on Wednesday, making him the latest high-ranking military official to depart the Trump administration.
Pentagon spokesman Sean Parnell confirmed the departure in a social media post, noting that Navy Undersecretary Hung Cao will serve as acting secretary. The role is largely administrative, overseeing policy, recruitment, training, and budgeting for the Navy.
While no official reason was provided, unconfirmed US media reports suggest tensions over shipbuilding issues led to Phelan's exit. Sources told multiple outlets that he clashed with Defense Secretary Pete Hegseth over implementing President Trump's shipbuilding initiative.
"On behalf of the Secretary of War and Deputy Secretary of War, we are grateful to Secretary Phelan for his service," Parnell wrote. "We wish him well in his future endeavors."
Phelan's departure follows a series of military leadership changes. Weeks earlier, Hegseth asked Army Chief of Staff Randy George to step down, and two other Army officials, Gen David Hodne and Maj Gen William Green, were removed. Since taking office, Hegseth has fired over a dozen senior military officers, including the chief of naval operations and the Air Force's vice chief of staff.
Phelan, a civilian businessman and major Trump donor, was sworn in as Navy Secretary in March 2025 after being nominated in 2024. He had supported Trump's plan for a new "Golden Fleet" of battleships named after the president, announced at Mar-a-Lago last December.
Andrew Peek, a former State Department deputy assistant secretary, suggested the ouster may be linked to slow progress on expanding the merchant and civilian fleet. "Eventually, somebody was going to take the fall for the lack of movement," he said, adding that 70% of the reason might be replacing Phelan with a trusted MAGA ally.
Acting Secretary Hung Cao, a 25-year Navy veteran, became undersecretary in October 2025. He unsuccessfully ran for US Senate in Virginia in 2024 on a Trump-endorsed campaign that criticized diversity, equity, and inclusion initiatives. During a debate, Cao said the Navy needs "alpha males and alpha females who are going to rip out their own guts, eat them and ask for seconds."
The leadership change comes amid ongoing US-Israel tensions with Iran and a continued US blockade of the Strait of Hormuz. Despite a ceasefire, clashes persist in the strategic waterway, with Iran claiming to have seized two ships. White House Press Secretary Karoline Leavitt said President Trump is "satisfied" with the blockade, while Iranian negotiator Mohammad Bagher Ghalibaf stated reopening the strait is impossible due to alleged ceasefire violations by the US and Israel.