$5 a Gallon? Brace Yourselves for High Gas Prices Says Ex-Shell CEO

John Hofmeister, former president of Shell Oil, warned this week that Americans could be paying as much as $5 for a single gallon of gasoline by 2012.

"I'm predicting actually the worst outcome over the next two years which takes us to 2012 with higher gasoline price," Hofmeister told Platt's Energy Week television, citing increasing global demand for oil.

CNN Money reports that while the price of gas is surely on the rise, it may not be quite as bad as Hofmeister predicts:

Tom Kloza, chief oil analyst with Oil Price Information Service says Americans will see gasoline prices hit the $5 a gallon mark in the next decade, but not by 2012.

"That wolf is out there and it's going to be at the door...I agree with him that we'll see those numbers at some point this decade but not yet." Kloza said.

"The demand is still sluggish enough in some of the mature economies."

Gasoline prices have been steadily rising. Last week, gas prices crossed the $3 mark for the first time since October 2008. According to AAA figures, prices are up 4% from a month ago and 16% from the $2.585 average a year ago.

A study from the Oil Price Information Service estimates drivers will spend $305 on gasoline in December. According to the study, fuel prices are up 13.6% from last December and 76% higher from December 2008.