Oil prices continued to drop Thursday after the U.S. government reported a large buildup in supplies of gasoline and diesel.

Benchmark U.S. oil for January delivery was down 7 cents to $97.37 in electronic trading on the New York Mercantile Exchange.

The contract fell $1.07 to close at $97.44 on Wednesday after the U.S. Energy Department's report on supplies. Anticipation of a fall in supplies had earlier driven prices up to a six-week high.

Gasoline supplies rose by 6.7 million barrels, the Energy Department said, while distillate supplies including diesel increased by 4.5 million barrels in the week ended Dec. 6.

Both increases were more than three times what analysts were expecting, raising the possibility that refiners would slow production and purchases of oil in the coming weeks.

The fuel increases overshadowed a huge decline in crude oil supplies of 10.6 million barrels.

Brent crude, a benchmark for international oils, was up 4 cents at $109.74 a barrel on the ICE exchange in London.

In other energy futures trading on Nymex:

— Wholesale gasoline was flat at $2.66 a gallon.

— Heating oil barely budged at $3.02 a gallon

— Natural gas rose 2.9 cents to $4.366 per 1,000 cubic feet.