NEW YORK – Oil prices fell again Monday on worries that fraud charges against Goldman Sachs could prompt a retreat from energy commodities to more safe-haven investments.

Traders also worried that disruption to air travel from the Icelandic volcano will reduce demand for jet fuel and could hamper the global economic recovery.

Meanwhile, crude oil's slide nudged gasoline prices slightly lower.

Benchmark crude for May delivery tumbled $1.79 to settle at $81.45 a barrel in electronic trading on the New York Mercantile Exchange. Earlier shares fell as low as $80.58.

Oil fell $2.27 to $83.24 a barrel on Friday after the Securities and Exchange Commission said Goldman Sachs & Co. defrauded investors by failing to disclose key information about mortgage investments it sold as the housing market was collapsing in 2008.

Investors were worried about how Goldman's predicament could affect commodity futures and speculated that Goldman may have to liquidate some positions in crude to pay penalties if found liable. Analysts believe that a sell-off from Goldman, a major player in oil trading, could spark a wider market retreat from crude oil futures.

Oil was trading around $87 per barrel about two weeks ago and there was talk among analysts of a run-up to triple digits. Some tepid U.S. economic data quelled that enthusiasm. And then the Goldman news hit.

"The allegations against Goldman Sachs could be the nudge required to push the market into a severe correction in the short term," said oil analyst Stephen Schork. With enough downward momentum, prices could fall as low as $78.32 by the end of the week, he said.

Meanwhile, a huge cloud of volcanic ash has shut down air traffic across most of Europe for four days - stranding passengers and scuttling international travel plans and freight services that could end up costing billions of dollars.

At the very least, traders say the volcano crisis will lower airlines' demand for jet fuel.

"The market had underestimated the impact of the volcano," said Clarence Chu, a trader with market maker Hudson Capital Energy in Singapore. "There's still a lot of uncertainty about how much this will affect the overall economy."

Falling crude prices have given U.S. motorists a break at the pump, as the national average gasoline pump price slid less than a penny to $2.862 a gallon, according to AAA, Wright Express and Oil Price Information Service. A gallon of regular unleaded is 4.4 cents more expensive than a month ago and 80.5 cents higher than a year ago.

In other Nymex trading in May contracts, heating oil fell 6.01 cents to settle at $2.1568 a gallon, and gasoline slid 2.26 cents to close at $2.2544 a gallon. Natural gas declined 9.5 cents to $3.944 per 1,000 cubic feet.

In London, Brent crude's June contract was down $1.76 to settle at $84.23 on the ICE futures exchange.

---

Associated Press writers Pablo Gorondi in Budapest, Hungary and Alex Kennedy in Singapore contributed to this report.