Crude-oil futures settled sharply lower Monday amid nagging concerns about global crude output and fears of an economic slowdown internationally that may erode demand.

February West Texas Intermediate CLG9, +1.50% fell $3.06, or 6.7%, to $42.53 a barrel on the New York Mercantile Exchange, after booking a weekly loss of 11.4% last week, according to Dow Jones Market Data. The U.S. benchmark contract on Monday finished at the lowest for a front-month contract since July 21, 2017.

Oil trading on Nymex ended at 1:30 p.m. Eastern Time, an hour earlier on the eve of Christmas, with global markets closed on Tuesday in observance of the holiday.

Meanwhile, February Brent LCOG9, +0.89% the global benchmark, declined $3.35, or 6.2%, to end at $50.47 a barrel, following a 10.7% weekly downturn for the oil contract.

Both grades of crude are in a bear market, usually defined as a decline of at least 20% from a recent peak. WTI oil is down 40.5% from its recent peak on Oct. 3, while Brent is off about 38% from its recent October high.

Evidence of sagging economic expansion across the globe, with the exception of the U.S., has resulted in bear markets cropping up in a number of stock markets, diminishing some appetite for assets perceived as risky, like oil. Receding global growth could lead to weaker energy demand.

U.S. stocks marked their worst daily declines on the trading day before the Christmas holiday in history, with the Dow Jones Industrial Average DJIA, -2.91% and the S&P 500 index SPX, -2.71% recording losses of nearly 3% on the day.

“We have such a risk-off appetite in the broader markets that crude’s only getting swept up in that sentiment as well,” Matt Smith, director of commodity research at ClipperData, told MarketWatch on Monday.

So far, efforts by Saudi Arabia, the de facto leader of the Organization of the Petroleum Exporting Countries, to limit output beginning early next year by 322,000 barrels a day — more than a previously announced cut of 250,000 barrels a day for six months starting in January, according to the Wall Street Journal — hasn’t adequately quelled concerns. Continued growth in U.S. crude production, notably by shale-oil producers, also has contributed to worries about a growing glut worldwide.

“Incredibly in the face of even deeper production cuts, petroleum markets have hit fresh lows. And while the production cut should restore a semblance of supply balance for the first half of 2019, global growth concerns and shale production, which continues to make new record highs, has investors deeply concerned,” wrote Stephen Innes, head of Asia Pacific trading at Oanda, in a research note dated Dec. 23.

ClipperData’s Smith said “there hasn’t been any real areas of support [for crude prices], so we are continuing to push levels to $44 or $42.

Elsewhere in the energy complex, January natural gas NGF19, -3.12% closed down 34.9 cents, or 9.2%, at $3.467 per million British thermal units, notching its steepest daily drop since Nov. 15. January gasoline RBF9, +1.32% settled 5.3% lower to end at $1.2488 a gallon, booking its lowest settlement since Feb. 29 of 2016.

January heating oil HOF9, +0.28% dropped 4.1% to settle at $1.6622 a gallon, representing its lowest finish since Aug. 28, 2017.