US Navy Secretary John Phelan is leaving the Trump administration, the Pentagon announced on Wednesday.

His departure will be "effective immediately", Pentagon spokesman Sean Parnell said in a social media post.

Navy Undersecretary Hung Cao will serve as acting secretary, Parnell added.

Phelan is the latest high-ranking military leader to leave the administration in recent months. His departure comes amid the US-Israel war with Iran and the continued US blockade of the Strait of Hormuz.

"On behalf of the Secretary of War and Deputy Secretary of War, we are grateful to Secretary Phelan for his service to the Department and the United States Navy," Parnell wrote. "We wish him well in his future endeavors."

The Navy did not provide a reason for Phelan's departure.

It comes just weeks after US Defense Secretary Pete Hegseth asked Army Chief of Staff Randy George to step down from his post.

Two other army officials, Gen David Hodne and Maj Gen William Green, have also been removed from their roles recently.

Since entering the Pentagon, Hegseth has fired more than a dozen senior military officers, including the chief of naval operations and the Air Force's vice-chief of staff.

Phelan, a civilian who had not previously served in the military, was sworn in as Secretary of the Navy in March 2025 after being nominated by President Donald Trump in 2024.

His replacement, Cao, became undersecretary in October 2025 and is a 25-year Navy veteran.

Cao ran an unsuccessful campaign for the US Senate in Virginia in 2024, endorsed by Trump, against incumbent Democratic Senator Tim Kaine.

The Navy's change in leadership comes as Trump said the US blockade of Iranian ports would continue amid a ceasefire in the war. Clashes have continued in the Strait of Hormuz, a vital global shipping route that supplies much of the globe's oil, with Iran announcing that it had "seized" two ships in the strait.

White House Press Secretary Karoline Leavitt said the president is "satisfied" with the ongoing US naval blockade on Iranian ports, and "understands Iran is in a very weak position".

Mohammad Bagher Ghalibaf, Iran's chief negotiator in talks with the US, said on Wednesday that it is "not possible" for the Strait of Hormuz to be re-opened due to "the blatant violations of the ceasefire" by the US and Israel.