Copper futures fell for the second time in three days as crude-oil prices slipped, dragging commodities lower.

Oil prices dropped as much as 0.9 percent after a U.S. government report showed crude output jumped to the highest in 20 years. Through yesterday, the dollar gained 0.4 percent against a basket of six currencies this year, reducing the appeal of commodities as alternative investments. The Standard & Poor’s GSCI Spot Index of 24 raw materials, which is weighted by more than 50 percent to energy products, was little changed in New York, erasing earlier gains.

“There’s a little nervousness in the markets over energy prices, and that’s affecting copper,” Sterling Smith, a futures specialist at Citigroup Inc. in Chicago, said in a telephone interview. “The dollar being back in positive territory also isn’t creating an ideal environment. None of this is giving any impetus for buyers to chase the market.”

Copper for delivery in three months decreased 0.1 percent to settle at $8,226 a metric ton ($3.73 a pound) on the London Metal Exchange. Zinc and lead were also lower in London, while aluminum, nickel and tin gained.

Financial markets are closed this week for the Lunar New Year holiday in China, the world’s biggest metals consumer.

“The China holiday has put a major participant in the markets on the sideline,” Smith said.

In New York, copper futures for March delivery declined less than 0.1 percent to close at $3.7425 a pound at 1:13 p.m on the Comex. The price has climbed 2.5 percent this year.

To contact the reporter on this story: Joe Richter in New York at jrichter1@bloomberg.net

To contact the editor responsible for this story: Steve Stroth at sstroth@bloomberg.net