“Acting Secretary Shanahan has proven over the last several months that he is beyond qualified to lead the Department of Defense, and he will continue to do an excellent job,” Press Secretary Sarah Sanders said.

Mr. Trump appointed Mr. Shanahan to the acting position in December as a replacement for his initial defense secretary, James Mattis, who resigned after clashing with the president over troop policy in Syria.

“I am honored by today’s announcement of President Trump’s intent to nominate,” Mr. Shanahan said. “If confirmed by the Senate, I will continue the aggressive implementation of our National Defense Strategy. I remain committed to modernizing the force so our remarkable soldiers, sailors, airmen, and Marines have everything they need to keep our military lethal and our country safe.”