After months of predictions, it finally happened on Wednesday. Crude oil hit the record $100 a barrel mark.

One of the main reasons given was increased rebel activity in Nigeria, one of the many troublespots from which the world draws supplies of its most important fuel.

The rebels did shut a number of production facilities in Nigeria, which did push up prices, but it's unlikely that they were the sole reason the record was broken.

In fact, the number of trades at $100 was so small that reports yesterday maintained it was two dealers on New York's commodities exchange who wanted to make history.

The price actually dipped to $99.62 by close of business on Wednesday, though figures showing that US crude stocks were lower than expected prompted another surge yesterday and oil futures hit a new record of $100.09 in New York yesterday morning.

As of last night Irish time, traders were paying $99.21 a barrel for crude due for delivery next month.

Some people question whether the record prices are sustainable.

Chicago-based commodities trader Phil Flynn told business newswire Bloomberg that some of the "euphoria" was beginning to wear off.

Part of the reason was further US government data showing that supplies of gasoline, a key refined product, had actually increased by 1.99 million barrels to 207.8 million barrels by the end of last week. Most observers had expected these supplies to increase by 1.5 million barrels.

The fact that it came within a whisker of two million allowed the market to breathe a sigh of relief.

In addition, supplies of distillate, which includes home heating oil and diesel, rose 569,000 barrels to 127.2 million barrels. These had been expected to fall.

Although US crude oil stocks were down by more than four million barrels, the price still dipped off the record highs. This was because it is the downstream products that the world's motorists and householders need, not the basic raw material.

Market analyst Kyle Cooper, of IAF Advisers in Houston, Texas, said these products were making a comeback. "I think we will see a surge in refinery output in a couple of weeks."

A lot of factors are driving oil prices. Maxol Ireland chief executive Tom Noonan said jittery stock markets have led to a "flight" into commodities, which investors see as a haven when equities are in trouble. "Oil is the classic commodity."

His argument is supported by the fact that another "classic", gold, which has few uses outside jewellery and electronics, hit a record high of $850 an ounce.

Noonan argues that this trend has boosted speculation in oil, which means that the price does not necessarily reflect the real supply and demand situation. Unfortunately, he acknowledges that oil prices are going to remain high for the foreseeable future.

And consumers will be reminded of this fact once again when they buy motor fuel or home heating oil over the next few days. The big suppliers of these products, such as Maxol, Topaz (owner of Shell and Statoil) and Texaco, are increasing their wholesale product prices.

The move will push petrol prices north of €1.20, depending where you buy it, and will add about €1 to the cost of filling the average car's fuel tank. The cost of filling a domestic heating oil tank will increase by about €100.

None of this is connected to crude's jump to $100. Instead it's related to prices paid last week for the refined products.

Still, one way or the other, it's clear that fuel prices are not going into reverse any time soon.