Construction costs for the Navy's proposed 355-ship fleet could ring in at more than $26 billion per year over 30 years, the nonpartisan Congressional Budget Office reported Monday. The Navy proposal tracks closely with President Trump's promise to build to a 350-ship Navy.

The annual shipbuilding cost, which would dramatically increase the service's current 275-ship fleet, is 40 percent more than what Congress approved in 2016 and dwarfs such annual ship spending over the past three decades, according to the CBO.

"To enlarge the Navy to 355 ships would require a substantial investment of both money and time," the CBO wrote in its report summary released Monday.

Trump campaigned on and has continued to call for a major military buildup, including a 350-ship fleet. The Navy floated its latest proposal late last year after an effort by the Obama administration to move toward a larger fleet.

The CBO examined the new larger proposal alongside the prior 308-ship goal in the report released Monday.

"The earliest the Navy could achieve its goal of a 355-ship fleet would be in 2035, or in about 18 years, provided that it received sufficient funding," the research service reported.

Building the ships would only be part of the overall cost.

When coupled with operational costs, the Navy would need a total of $102 billion per year through 2047, which is about 30 percent more than what it costs to keep its current 275 ships afloat. Plus, there are aviation costs to consider.

"Over the next 30 years, buying additional fixed-wing aircraft and helicopters to outfit the additional 63 ships would require $15 billion more than the Navy would spend on aircraft under its existing [308-ship] plan," the CBO found.

That does not include the cost of weapons, munitions, drones and shipyard improvements that would also be required.

It is unclear whether Congress could cobble together the billions in new funding.

The Navy — and the services in general — have been struggling to maintain training and current equipment due to years of federal spending caps passed by lawmakers in 2011.