President Trump unveiled plans for a $22.5 billion redesign of Dulles International Airport at the White House on Wednesday, characterizing the reconstruction as part of his broader efforts to remake the Washington region.

“This transformation is another step in our ongoing efforts to make Washington, D.C., safe and beautiful again,” Mr. Trump said, adding that the project would have bipartisan appeal, because “whether you’re Republican or Democrat, you don’t want to go and be subjected to this airport.”

Dulles Airport, which opened in the Virginia exurbs of Washington in 1962, has long been celebrated as an architectural landmark, thanks to the sweeping glass features of the main terminal, designed by the Finnish American architect Eero Saarinen. Mr. Trump called that terminal “iconic,” and he said that it would be spruced up but preserved as part of the redesign.

But the expansion of the airport in the years since it opened made navigating it an awkward experience for many, due in large part to the separation of the various concourses and the airport’s reliance on a fleet of buses, known as people movers, to ferry passengers between the concourses and the main terminal.

“It’s an impossible airport: You go off a bus, you get into a train; you get off of a train, you get into another bus,” Mr. Trump said to reporters, expressing a frustration common to many travelers through Dulles.

In the redesign, which officials said would not require federal spending, the concourses would be connected by a central walking tunnel and a new air train, Mr. Trump and his transportation secretary, Sean P. Duffy, explained. A new hotel would be built on the airport campus, the C and D terminals would be replaced, and the airport would be outfitted with new restaurants and shops, as well as a large United Airlines lounge.

United Airlines and the Metropolitan Washington Airports Authority submitted the design that Mr. Trump ultimately settled on after reviewing more than 30 proposals, according to a Transportation Department spokesman. Dulles Airport is one of United Airlines’ main hubs.

The airport redesign also includes plans for a 32,000-space parking garage, which Mr. Trump repeatedly bragged would make it the largest in the world. The added capacity would come as the airport had sought to ease vehicle congestion, having recently connected to the metro transit system that serves the nation’s capital.

In all, the project would encompass more than five million square feet of new and renovated space, Mr. Trump said, and take about two years to complete. Mr. Duffy said that administration officials “think we can start construction in the spring of next year.”

But there are financial and regulatory hurdles left to clear, even as officials said the project would not need federal spending.

Mr. Trump told reporters that “cost was no object” in finalizing the design, and Jack Potter, the president and chief executive of the Metropolitan Washington Airports Authority, said that it could be completed “not requiring federal dollars.”

“This is going to be airport-generated dollars, airline contributions,” Mr. Potter said.

While the project is bonded at $22.5 billion, there are still certain permissions that the administration must secure from Congress before forging ahead, Mr. Duffy noted. The Airports Authority operates Dulles under a lease from Congress, which, according to the authority, is not set to expire until 2100.

It is also not clear whether Mr. Trump would try any further personal intervention in the project as it proceeds.

Earlier this year, White House officials tried to pressure Senator Chuck Schumer, Democrat of New York and the minority leader, into helping Mr. Trump rename Dulles Airport after himself, dangling billions in frozen funds for a rail tunnel under the Hudson River as leverage.

As Mr. Trump showed off an architectural model of the envisioned changes on Wednesday and boasted about the details of “a modernization of Dulles that’s sorely needed,” he made no mention of potentially changing the name.

There is at least one Republican-sponsored bill pending before the House to affix Mr. Trump’s name to the airport.