WASHINGTON - Consumers helped boost economic growth in the final months of last year, but higher oil prices are threatening to steal some of that momentum this year.

More expensive gas will dampen consumer spending, at least in the first three months of this year. Still, many economists say the bump in fuel costs and the crisis in Japan will have only a mild impact on the U.S. economy for the full year and are sticking with 2011 projections for the fastest growth since before the recession.

Economic growth

The economy, as measured by the gross domestic product, grew at an annual rate of 3.1 percent in the October-December quarter, the Commerce Department reported Friday. That was an upward revision from last month's 2.8 percent estimate, boosted by more inventory building and business investment in plants and equipment.

The quarterly expansion was the best since the start of last year and was driven by 4 percent growth in consumer spending, the strongest gains in four years. Consumer spending is closely watched because it accounts for 70 percent of economic activity.

Many economists had high expectations for growth this year after President Barack Obama signed into law a one-year tax cut that will give most Americans an extra $1,000 to $2,000.

But a jump in oil prices has likely cut into the gains from the tax cut, slowing growth in the first three months of this year. How much is a matter of debate, reflected in the wide range of estimates for growth in the January-March quarter. Forecasts range from as low as 2.3 percent to as high as 3.8 percent.