New York City Mayor Michael Bloomberg has ordered the emergency rationing of fuel due to a severe shortage caused by Superstorm Sandy.
Based on license plates ending in odd or even numbers, drivers will be allowed to buy fuel on alternating days, Bloomberg announced at a briefing.
Licenses ending in a letter are eligible to buy gas on odd-numbered days, he said.
The system, which follows a similar rationing regime implemented in New Jersey last week because of Sandy, begins at 6am on Friday (local time) in all of the city's five boroughs, he said.
It will remain in effect until further notice.
The region has been hard hit by fuel shortages since Sandy hit ten days ago, due to power outages and inventory that has been stranded at refineries and terminals.
"Last week's storm hit the fuel network hard and knocked out critical infrastructure needed to distribute gasoline," the mayor said in a statement.
He called the rationing system "the best way to cut down the lines and help customers buy gas faster."
Bloomberg said only a quarter of the city's gas stations are open. His count was far lower than the estimate by the AAA automotive organisation that 65 to 70 percent of the city's nearly 800 stations were open and sold gas on Thursday.
A spokesman for the mayor said City Hall was estimating the number of retail stations that were open at any given time, while the AAA count included stations that may have had gas at least once during the day but may have run out of fuel and closed.
Emergency vehicles, buses, taxis and certain other vehicles are exempt from New York City's rationing system.
In New Jersey, Governor Chris Christie announced an odd-even rationing system for 12 counties that began on Saturday.
