Officials Outline Beefed-Up Security Plan for Area Around Trump Tower in New York City

"This is a big challenge and an unprecedented challenge," the mayor said.

— -- The fortified area around Trump Tower in New York City is in for beefed-up security measures from now until Inauguration Day, according to city and federal officials who spoke at a news conference this afternoon.

The volume of pedestrians that cross the intersection by Trump Tower is "probably some of the highest in the Western world," said Department of Transportation Commissioner Polly Trottenberg. She added that 140 buses run through Fifth Avenue during the morning rush hour.

Trump's presidential transition, at the height of the holiday season, "adds a layer of complication," de Blasio said.

The mayor urged people to avoid Fifth Avenue from 60th Street to 53rd Street if they could for the next 65 days. He said that the city is committed to helping businesses thrive, but safety and security remains the priority.

De Blasio added that law enforcement would be in communication with local residents and businesses to address concerns and keep traffic -- both pedestrian and vehicular -- "moving as well as possible."

Both de Blasio and NYPD Commissioner James O'Neill said that the city would be seeking reimbursement from the federal government for the costs of the "substantial" amount of resources the new security plan requires.

"We are particularly concerned about overtime costs," de Blasio said.

Despite the multiple challenges, Secret Service Special Agent David Beach said that he could think of "no city better equipped, better prepared to deal with this challenge than New York."