US Navy Secretary John C. Phelan departing administration: Pentagon

US Secretary of the Navy John C. Phelan is departing the administration "effective immediately," Pentagon spokesman Sean Parnell said Wednesday.

"We are grateful to Secretary Phelan for his service to the Department and the United States Navy. We wish him well in his future endeavors," Parnell said in a statement

Undersecretary Hung Cao will become acting secretary of the Navy, he added.

Phelan was tapped for the post by President Donald Trump last year and was confirmed by the Senate in a 62-30 vote.

During his confirmation hearing before the Senate Armed Services Committee, he pledged to work to improve the US Navy by addressing recruitment and retention in the branch as well as increase the Navy's fleet among other issues.

The Wall Street Journal, citing US officials, reported that Phelan was fired after months of simmering tensions with Defense Secretary Pete Hegseth.

Phelan’s firing comes after a rocky tenure under Hegseth and Deputy Defense Secretary Steve Feinberg, including tension over Phelan’s close relationship with Trump, according to three people familiar with the internal discussions, the report said.

The top Pentagon leaders were particularly annoyed last fall when Phelan pitched the idea for a modern battleship directly to Trump, bypassing Hegseth, the people said, according to the report.

They added that since then, Hegseth and Feinberg have worked to undermine Phelan by creating a new czar for submarine acquisition who reports directly to Feinberg.

Hegseth has dismissed a number of officials during Trump’s second term.

In early April, the Pentagon announced that Gen. Randy A. George will retire from his role as the 41st Chief of Staff of the Army "effective immediately."

More than a dozen senior military officers have been fired by Hegseth, including Joint Chiefs of Staff Chairman Gen. C.Q. Brown Jr., Chief of Naval Operations Adm. Lisa Franchetti, Air Force Vice Chief of Staff Gen. James Slife and Defense Intelligence Agency head Lt. Gen. Jeffrey Kruse.

According to local media reports, Phelan is the 34th military officer that Hegseth has fired since taking office.