NEW YORK (Reuters) - New York City will end gas rationing at dawn on Saturday, nearly four weeks after superstorm Sandy led to a regional fuel shortage, Mayor Michael Bloomberg said on Friday.

The odd-even system based on license plate numbers, was launched on November 9 to help cope with fuel shortages and long lines at gas stations after the storm. As of Friday, more than 85 percent of the city's gas stations were operational, the mayor said in a statement.

Also on Friday, 27 people were treated for smoke inhalation after a fire broke out in the basement of a high-rise office building in lower Manhattan that had been without power since the storm.

A spokesman for the city fire department said the cause of the fire was not immediately known.

(Reporting By Edith Honan; Editing by Peter Cooney)