Crude oil prices hit another record high in Thursday's New York trading.

Prices went as high at $72.49 a barrel before retreating slightly.

Oil also reached a new record in London trading.

Oil prices have been rising recently, spurred by tensions over Iran's nuclear program and concern about continuing violence in Nigeria.  Both Iran and Nigeria are major oil suppliers.     

In the United States, the world's largest oil consumer, there are additional worries that refineries might not be able to meet gasoline demand after the government ordered changes in fuel formulas to ease environmental problems.

Some information for this report was provided by AFP, AP and Reuters.