The freak storm, due to come ashore in the United States late on Monday, is forecast to bring thrashing winds, flash flooding and even heavy snowfall.

"Hurricane Sandy is causing disruption, flight delays and cancellations throughout the Eastern Seaboard of the U.S.A.," the airline said in a statement on its website.

"We understand that customers may be disappointed, however their safety is our highest priority. We are offering the option to re-book or receive a refund to those customers whose flights are cancelled."

Dubbed "Frankenstorm", Sandy's effects are expected to reach from the Mid-Atlantic states to New England. It could be the largest storm to hit the United States, according to the National Oceanic and Atmospheric Administration's website.

Schools, businesses and transport systems have prepared to close in preparation for the arrival of the storm, which killed at least 66 people as it passed through the Caribbean. (Reporting by Isla Binnie; Editing by Dale Hudson)

• A Permanent Economic Emergency