Updated from 1:23 p.m. EDT
Oil prices erased an early loss Tuesday and regained the $55-a-barrel level.
According to preliminary data, the December futures contract closed 63 cents higher at $55.17, matching the previous record high, in regular floor trading on the Nymex.
Prices had been down more than 1% early in the session,after the Norwegian government ordered an end to an oil workers' strike, the second in recent months.
Prices closed above $55 for the first time ever last Friday, the latest in a seemingly endless parade of record highs since May. The intraday high, also touched on Oct. 22, is $55.43.
With winter looming, heating oil prices also have been soaring, reflecting market concerns about supply during a period of unusually strong global demand.
U.S. production is still recovering from the widespread disruption of Hurricane Ivan as it swept through the energy-rich Gulf of Mexico in September. Key weekly invenory data are due out tomorrow morning.
In addition, periodic sabotage attacks on Iraqi oil facilities, which have slowed or halted exports from time to time, are now a fundamental market concern.