The Group of 20, or G20 Leaders Summit, will be held in South Florida and requires high-level planning. Federal and local law enforcement agencies came together Monday to start public messaging ahead of the massive security operation in December.

The summit will be held Dec. 14-15 at Trump National Doral and is expected to bring some of the world’s most powerful leaders to Miami-Dade County. While officials have not yet released specifics about road closures or security zones, they are warning residents to expect traffic changes in Doral.

“Expect an increased law enforcement presence throughout the city and the surrounding areas,” Miami-Dade Sheriff Rosie Cordero-Stutz said. “That visibility is a sign of preparedness.”

Federal, state and local agencies are already coordinating security plans for the summit. Officials invited NBC6 inside the FBI’s Miami field office for a preview of the preparations that are already underway.

The G20 summit brings together the world’s major economies to strengthen international cooperation and address global economic issues.

“South Florida is no stranger to large-scale special events, coming off the heels of the FIFA World Cup,” FBI Special Agent in Charge Brett Skiles said. “We’ve been coordinating closely with our partners in preparation for this event.”

The summit has been designated a National Special Security Event, or NSSE. That designation is given to events of national significance that may present potential security risks and require extensive federal resources.

The U.S. Secret Service will serve as the lead federal agency responsible for coordinating security for the summit, working alongside dozens of federal, state and local partners.

The list of participating countries includes Canada, China and Russia, with an invitation extended to Russian President Vladimir Putin.

NBC6 asked officials how the international political landscape could influence security planning for the summit.

“You’ll have 85% of the world’s GDP in one place, so that’s the significance of this event,” said Joseph “Sonny” Berrios, the U.S. Secret Service G20 coordinator. “Our responsibility is not just for one single protectee. It’s for the community, the entire event and everybody attending.”

Secret Service officials said the security operation will extend beyond Doral’s city limits.

“We are working with many agencies, including the FBI, FEMA, the state of Florida, Miami-Dade, Broward, Palm Beach counties and the city of Doral,” said U.S. Secret Service Acting Special Agent in Charge, Michael Townsend.

Some of the most extensive security measures, however, may not be visible to the public. Intelligence agencies are working behind the scenes to prepare for potential threats.

“These efforts are focused on assuring that if a response is required, it’ll be executed in a smooth, timely and well-coordinated manner,” said Skiles.

Officials said they are still determining which roads will be affected and when. More information about traffic, security restrictions and other impacts is expected as the summit approaches.

“We ask residents and visitors to remain patient, plan ahead, follow the guidance of local public safety agencies,” said Townsend.

The city of Doral is expected to release additional information about its preparations in the coming weeks, including during a news conference scheduled for Oct. 28.