NEW YORK — Oil prices rose to around $73 a barrel Wednesday after a survey of the petroleum industry said U.S. crude supplies dropped unexpectedly last week and the dollar weakened against other currencies.

Benchmark crude for January delivery added 34 cents to $72.96 on the New York Mercantile Exchange. In London, Brent crude for January delivery rose 7 cents to $75.26 on the ICE Futures exchange.

Crude prices rose overnight after the American Petroleum Institute said its survey of oil companies estimated that crude stocks fell 5.8 million barrels. Analysts had expected an increase of 600,000 barrels, according to a survey by Platts, the energy information arm of McGraw-Hill Cos.

The Energy Department's Energy Information Administration plans to announce its inventory report later Wednesday.

Traders were also eyeing the U.S. dollar. Crude is priced in dollars, and a strengthening greenback makes it more difficult for investors holding foreign currencies to buy energy commodities.

At the pump, retail gas prices dipped slightly to a new national average of $2.633 a gallon, according to auto club AAA, Wright Express and Oil Price Information Service. A gallon of regular unleaded is 3.1 cents cheaper than it was last month, but it is 93.5 cents more expensive than a year ago.

In other Nymex trading in January contracts, heating oil lost less than a penny to $1.9862 a gallon while gasoline gained less than a penny to $1.9274 a gallon. Natural gas gave up less than a penny to $5.109 per 1,000 cubic feet.

Associated Press writers Pablo Gorondi in Budapest, Hungary and Alex Kennedy in Singapore contributed to this report.