Six US states have declared emergencies as they prepare for the imminent arrival of Hurricane Irene which has left a trail of destruction across the Caribbean.

Having battered the Bahamas the first major storm of the Atlantic hurricane season has prompted states of emergencies in North Carolina, Maryland, Virginia, Delaware, New Jersey and New York.

Mandatory evacuations have been ordered in parts of Delaware, Maryland, New Jersey and North Carolina as Irene approaches bringing with it winds of at least 115mph .

The huge storm is creating hurricane force winds extending 80 miles from its centre, and tropical storm winds reaching up to 295 miles from the eye, according to the US National Hurricane Centre.

Forecasters said Irene could strengthen slightly throughout today (Friday) before its expected arrival in North Carolina on Saturday.

The hurricane, which has forced cruise lines to amend itineraries across the Caribbean and airlines to revise schedules, is then expected to weaken as it moves up the US east coast, diminishing in strength to a still-powerful category two storm on Sunday.

Up to 25 cruise ships in the Eastern Caribbean and Bahamas have had to change schedules affecting companies including Carnival Cruise Lines, Celebrity Cruises, Holland American Line, Norwegian Cruise Line and Royal Caribbean.

The Miami-based Hurricane Centre’s former director Max Mayfield told the Associated Press news agency: “One of my greatest nightmares was having a major hurricane go up the whole north east coast.”

He predicted that the damage could climb into billions of dollars, saying: “This is going to have an impact on the US economy.”

New Jersey Governor Chris Christie warned holidaymakers to avoid the shore, and urged people to evacuate ahead of the storm’s anticipated arrival on Saturday night.

New York City Mayor Michael Bloomberg urged residents of low-lying and beach-front areas to find a place to stay on higher ground ahead of Irene’s anticipated arrival on Sunday. The city is even planning to shut down the entire transportation system.