A sleek, modern terminal is coming to one of the busiest international airports in the U.S. and it could ease passenger congestion as soon as 2021.

Newark Liberty International Airport is forging ahead with a $2.7 billion redevelopment plan to overhaul its oldest terminal and build a one-million square-foot terminal with 33 gates and a new 3,000-car parking garage.

The project, named Terminal One, broke ground last June. Last week, the Board of Commissioners for the Port Authority of New York and New Jersey, which operates the airport, approved additional funding and picked the team that will design and construct the terminal for $1.41 billion: Tutor Perini Corporation and Parsons Transportation Group Inc.

All told, Terminal One is expected to create more than 23,000 jobs, $1.9 billion in wages and spur $4.6 billion in economic activity in the area, according to estimates by the Port Authority.

"There has been a continuous surge in the number of passengers at Newark Liberty, which last year welcomed more than 40 million of them," Port Authority Chairman Kevin O'Toole said in a statement, adding that the current terminal could no longer accommodate growing traveler needs.

Terminal A, which will be upgraded and renamed Terminal One, is the older of three terminals at the airport, according to a briefing book on the project. In 2016, the terminal served 10.6 million annual passengers.

Terminal One is estimated to have a partial opening in 2021 and be in full operation by 2022, officials said.

The planned upgrades will reduce passenger congestion with new roadways and a pedestrian bridge. The 45-year-old airport will also get new dining and retail spaces as well as updated technology.

Construction is already underway on three roadway bridges.

Karen Yi may be reached at kyi@njadvancemedia.com. Follow her on Twitter at @karen_yi or on Facebook.