President Donald Trump declared on Friday that an emergency exists in Georgia and ordered federal assistance to the state in advance of Hurricane Irma.

According to the White House, the president’s action authorizes the Department of Homeland Security, Federal Emergency Management Agency (FEMA), to coordinate all disaster relief efforts.

Earlier on Friday, six members of Georgia's congressional delegation sent a letter to the White House, urging the president to expedite Gov. Nathan Deal's request for federal assistance in the 30 counties now under a state of emergency.

The letter was signed by both of Georgia's U.S. senators, Johnny Isakson and David Perdue, as well as U.S. Reps. Buddy Carter (R-1); Drew Ferguson (R-3); Austin Scott (R-8); and Rick Allen (R-12).

"This action will help alleviate the hardship and suffering that the emergency may inflict on the local population, and provide appropriate assistance for required emergency measures, to save lives, protect property, and ensure public health and safety, and to lessen or avert the threat of a catastrophe in the counties of Appling, Atkinson, Bacon, Brantley, Bryan, Bulloch, Burke, Camden, Candler, Charlton, Chatham, Clinch, Coffee, Echols, Effingham, Emanuel, Evans, Glynn, Jenkins, Jeff Davis, Liberty, Long, McIntosh, Pierce, Screven, Tattnall, Toombs, Treutlen, Wayne, and Ware," according to the White House.

Watch and read: President's message on Hurricane Irma

Debris removal and emergency protective measures, including direct federal assistance, will be provided at 75 percent federal funding.

Also on Friday, Gov. Nathan Deal said Irma could be more destructive than last year's Hurricane Matthew.

"This is considered an extremely dangerous, category 4 hurricane, with winds of more than 150 miles per hour,” Deal said in a news conference with other state officials. “We all remember the tremendous levels of destruction from Hurricane Matthew, and this one has the potential to be even more devastating to our state.”

On Thursday, Deal activated 5,000 National Guardsmen to be on call, and expanded the number of counties under a state of emergency to 30.

Deal said on Friday that it is "very likely" that number could be expanded.

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