President Donald Trump's first budget will call for a $54 billion increase in defense spending and a corresponding cut in what his administration deems lower priority programs, White House budget officials told reporters Monday.

The defense buildup that Trump repeatedly promised on the campaign trail would mark about a 10 percent spending hike. Under Trump's proposal, most federal agencies would face budget reductions, an Office of Management and Budget official said. Foreign aid spending would also drop.

The officials, who spoke on the condition of anonymity at the White House's insistence, did not say which federal departments would see the biggest cuts.

White House Budget Director Mick Mulvaney emphasized that the budget details reported Monday are a "blueprint" and that the "full blown" budget won't come until May.

Mulvaney said, however, that the budget blueprint is "the president's policies as reflected in topline discretionary spending."

"To that end, it is a true America first budget. It will show the president is keeping his promises and doing exactly what he said he was going to do when he ran for office," Mulvaney said during a Monday news conference.

Speaking at a meeting with governors Monday, Trump said his administration will "do more with less and make the government lean and accountable."

The budget "will include a historic increase in defense spending to rebuild the depleted military of the United States of America at a time we most need it," Trump said at the White House.

Trump will give more details on his budget priorities in an address to a joint session of Congress on Tuesday night.

Trump has not officially introduced his budget but will start a discussion with agencies about how much money will be cut, an OMB official said. Trump plans to submit his desired defense budget and agency spending cuts to Congress next month. Congress ultimately passes the budget that the president signs.

The initial budget proposal will not address tax reform or mandatory spending.

The New York Times previously reported that Trump's White House wants big cuts at the Environmental Protection Agency and State Department. The administration also wants cuts for some social safety-net programs, but not the large entitlement programs for retirees, the Times said.

The U.S. spends the most money on defense of any country in the world by far. Some defense experts have wondered about the need for a major spending increase in a country with an annual defense budget of nearly $600 billion.

The total annual spending for the State Department and foreign aid is about $50 billion, according to Reuters.



Defense stocks Lockheed Martin, Northrop Grumman and Raytheon all climbed after Trump's statement.

﻿—CNBC's Christine Wang, and Reuters contributed to this report.