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 on an acting basis in the role, which is largely administrative.

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.

The Navy has not provided a reason for Phelan's exit, which reportedly followed tensions over shipbuilding issues, based on unconfirmed media reports. 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 stated. We wish him well in his future endeavors.

Just weeks prior, Defense Secretary Pete Hegseth requested Army Chief of Staff Randy George to resign, and two other Army officials have also been removed from their roles recently. Since joining the Pentagon, Hegseth has dismissed over a dozen senior military officers, including the chief of naval operations and the Air Force's vice chief of staff.

Phelan's resignation follows reported clashes with Hegseth regarding Trump's shipbuilding initiative. The secretary's responsibilities include formulating policies, recruiting, training, and equipping the Navy, overseeing budgeting, and logistics related to naval ships and facilities.

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

The change in leadership arrives as the US continues its blockade of Iranian ports and amidst ongoing conflicts in the Strait of Hormuz, a crucial oil shipping route.

White House Press Secretary Karoline Leavitt confirmed the president's satisfaction with the blockade, asserting that Iran is currently in a weak position.

As tensions persist in the region, the Navy's leadership transition will be closely monitored in the weeks ahead.

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