President Trump on Wednesday announced his selection of Philip Bilden, the head of a private equity firm, to serve as secretary of the Navy.

"As secretary of the Navy, Philip Bilden will apply his terrific judgment and top-notch management skills to the task of rebuilding our unparalleled Navy," Trump said in a statement. "Our number of ships is at the lowest point that it has been in decades."

Bilden, who works for the global private equity firm HarbourVest, is a former Army officer and has never served in the Navy. He serves as chairman of the Asia Advisory Council for the Emerging Markets Private Equity Association and is on the board of visitors for Georgetown University and Asia Pacific Advisory Board of Harvard Business School.

"I am deeply humbled and honored to serve as secretary of the Navy," Bilden said Wednesday. "Maintaining the strength, readiness, and capabilities of our maritime force is critical to our national security. If confirmed, I will ensure that our sailors and Marines have the resources they need to defend our interests around the globe and support our allies with commitment and capability."

As Navy secretary, Bilden will be the civilian chief of the Navy and Marine Corps. Bilden's selection was a shock to observers who believed former Rep. Randy Forbes, R-Va., was the natural choice for Navy secretary. Forbes, who lost his primary bid last year to Rep. Scott Taylor, was a forceful advocate for shipbuilding as head of the House Armed Services' seapower subcommittee. His former district includes Norfolk, the largest Navy base in the country, and Huntington Ingalls Industries, the nation's sole manufacturer of aircraft carriers.

If confirmed, Bilden will oversee Trump's plans to build the Navy from its current size of 274 ships and put it on a path toward about 350.

Rep. Rob Wittman, R-Va., and chairman of the House Armed Services Seapower and Projection Forces Subcommittee, called Bilden a "fitting choice" because of his commitment to rebuild the Navy and its readiness, and said he looked forward to working with him to build to the 355-ship fleet the Navy said it needed in its most recent force structure assessment.

"He will serve as our Navy's secretary during a time when we are witnessing China's unprecedented militarization of unclaimed islands in the South China Sea as well as Russia's expansion of its naval fleet, particularly in the undersea domain. These challenges must be met, and America's Navy will be relied upon to provide presence, deterrence, and reassurance to our allies in these strategically important regions," Wittman said.

By choosing Bilden, Trump finalizes his roster for the three service secretaries. He has already nominated business executive Vincent Viola for Army secretary, and this week named former New Mexico Rep. Heather Wilson to be his Air Force secretary. Viola graduated from the Military Academy at West Point and Wilson is an Air Force Academy graduate.

Defense Secretary James Mattis said each nominee will have his "full support" as they face confirmation by the Senate.

"All three of these nominees have my utmost confidence," Mattis said. "They will provide strong civilian leadership to strengthen military readiness, gain full value from every taxpayer dollar spent on defense, and support our service members, civilians, and their families."

Gabby Morrongiello and Jacqueline Klimas contributed to this report.