At the pump, gasoline prices nationally and in the Philadelphia-South Jersey area were unchanged yesterday from Monday, but appeared poised to rise to new records of their own in coming weeks.

The new Goldman Sachs Group Inc. prediction that oil prices could rise to $150 to $200 a barrel within two years seemed to motivate much of yesterday's buying, although a falling dollar and increasing concerns about declining crude production in Mexico and Russia contributed, analysts said.

The Energy Department raised its oil and gasoline price forecasts, but it also predicted that high prices would cut U.S. demand more than previously thought.

Light, sweet crude for June delivery jumped to a record closing of $121.84 on the New York Mercantile Exchange. During the day's trading, the price hit $122.73 a barrel before retreating.

Oil prices have nearly doubled from about $62 a barrel a year ago, which Goldman said was a sign that the world was in the midst of a "super-spike" in oil prices.

But Tim Evans, an analyst at Citigroup Inc., countered Goldman's analysis with a note predicting that crude prices could as easily fall to $40 a barrel as rise to $200 over the next two years, because supplies are, as Evans put it, comfortable.

But some investors respond to such predictions by buying, said James Cordier, president of Tampa, Fla., trading firms Liberty Trading Group and OptionSellers. com.

Meanwhile, in a monthly report, the Energy Department's Energy Information Administration predicted oil prices would average $110 a barrel this year, up $9 from a forecast a month ago. The agency also said high prices would cut U.S. demand for petroleum products 330,000 barrels a day this year; last month, the agency predicted U.S. petroleum consumption would fall 210,000 barrels a day.

But strong demand for oil from countries such as China, India, Russia, Brazil and from the Middle East will support high prices and keep global oil demand growing about 1.2 million barrels a day this year, unchanged from last month's forecast, the energy agency said.

The national average price of a gallon of regular gas at the pump remained at $3.61, according to AAA and the Oil Price Information Service.

In the five-county Philadelphia area in Southeastern Pennsylvania, yesterday's average was $3.65 a gallon, and it was $3.47 in the three suburban counties in South Jersey, both the same as Monday, according to AAA Mid-Atlantic.