Crude oil prices climbed sharply Tuesday morning, topping $87 per barrel two days after the start of the European Union\'s embargo against Iran. The immediate impact on supply is unclear. Several producers have said they would ramp up production to make up for oil lost as a major market quits buying from Iran to force negotiations on the country\'s alleged nuclear weapons program. On the other hand, economic data in the United States and Europe show manufacturing is slowing down in reaction to the uncertain economic conditions. West Texas Intermediate crude oil added $3.57 on the New York Mercantile Exchange to $87.32 per barrel. Home heating oil prices gained 7.06 cents to $2.7465 per gallon. Reformulated blendstock gasoline hit $2.7093 per gallon, up 8.54 cents. Natural gas for July delivery reached $2.868 per million British thermal units, up 4.4 cents. At the pump, the national average price of unleaded gasoline rose to $3.329 per gallon Tuesday from Monday\'s $3.326, AAA said.