NEW YORK ( TheStreet) -- Crude oil prices were pressured from multiple directions Monday, losing 2% as Goldman Sachs' ( GS) legal travails continued to weigh, as did concerns about weaker jet fuel demand resulting from restricted flying conditions in Europe. The Securities and Exchange Commission charged Goldman Sachs with fraud on Friday, which immediately hit financial and basic materials sectors. Although financials seemed to be recovering Monday, helped by a surprise first-quarter profit from Citigroup ( C), the basic materials sector was Monday's weakest. Some market watchers believe that Goldman's position as one of the largest commodity brokers accounted for the sector's weakness in recent sessions. Also impacting commodities was a stronger U.S. dollar as uncertainty in the U.S. coupled with continued concerns about Greece sent the dollar higher as investors fled from riskier assets. The dollar index rose 0.14 to 80.94. The front-month May delivery crude contract lost $1.79, or 2.2%, to settle at $81.45 a barrel, while the more actively traded June delivery contract shed $1.54, or 1.8%, to settle at $83.13 a barrel. "It appears there's some further agitation on the civil suit with Goldman," said Gene McGillian, analyst at Tradition Energy, of oil prices. "Is the problem with Goldman something serious or something only Goldman will have to deal with? All of this stuff can take on a life of their own, so we'll have to keep an eye on them." Still, McGillian also notes that "the selloff may have a little more to do with technicals" and a casual trend. In recent weeks, the crude contract has stayed within a trading range, rising on optimism only to fall after investors reconsider continually high inventory levels. "The market is able to move through recent highs and gets a little above there," McGillian adds. "Then the real underlying fundamentals aren't supportive of the length and then moves down and then game starts up again." Five days after volcanic ash from an eruption in Iceland grounded flights to and from Europe , airlines appeared to be resuming flights. Grounded planes were cited as a possible reason why crude prices have shown recent weakness because it means less demand for jet fuel, though McGillian insists the long-lasting impact on oil markets is negligible. Separately, Barclays Capital analyst Amrita Sen agreed. "In our view, the impact of the current losses in jet fuel demand totals about 1.1 million to 1.2 million barrels per day. With two-thirds of flights cancelled, this amounts to roughly 700,000 barrels a day, and even including a very generous allowance for the rest of the world -- from where flights to Europe have been cancelled -- this total would rise to just about 1 million barrels per day," Sen said. "In a global oil market of 85 million barrels per day, the disruption so far is likely to have limited consequence on an annual basis, especially if one puts this into perspective of the widely divergent views on European oil demand projections." Energy stocks were among the session's laggards. The Philadelphia Oil Service Sector index lost 0.3% although the NYSE Arca Oil index managed a gain of 0.07%. On the Dow Jones Industrial Average, Chevron ( CVX) shares gained 60 cents, or 0.7%, to $81.32 and Exxon Mobil ( XOM) added 31 cents, or 0.5%, to $68.24. Shares for oil servicing firm Halliburton ( HAL) lost 7 cents, or 0.2%, to $31.57 after reporting a profit tumble over 45% in the first quarter since last year. Weatherford International ( WFT), another oil servicer, reports first-quarter earnings Tuesday. Analysts are looking for a profit of 9 cents a share. The stock dropped 25 cents, or 1.5%, to $16.28. Arch Coal ( ACI), which missed first-quarter profit forecasts in the morning while offering encouraging earnings guidance for 2010, saw shares advance by 4 cents, or 0.2%, at $26.04. Also on the Nymex, the May delivery contract for natural gas lost 10 cents, or 2.4%, to $3.94 per million British thermal units. May heating oil was down by 6 cents, or 2.7%, to settle at $2.16 a gallon and May gasoline shed 2 cents, or 1%, to settle at $2.25 a gallon. --Written by Sung Moss and Melinda Peer in New York.