NEW YORK (Reuters) - Nearly two-thirds of all the service stations in New York City and New Jersey remain shut, due mostly to a lack of power following Hurricane Sandy, the AAA said on Friday in data that showed little improvement from a day ago.

The organization said that although average gasoline prices in the area had risen by just about 1 cent versus Thursday, compared with a nationwide price drop of about 1 cent, prices had risen by an average of about 5 cents on Long Island, where only 30 to 35 percent of all service stations were operating.

"The primary issue faced by motorists is not a lack of supply - rather it is a lack of electricity to pump gasoline into tanks," a AAA spokesman said in an email. "AAA expects that long lines and supply issues will diminish once power is restored to the region in the coming days."

(Reporting By Jonathan Leff; Editing by Gerald E. McCormick)