New York: The price of oil extended losses Friday as seasonal maintenance of refineries crimps US demand and a stronger dollar makes the commodity more expensive.

Benchmark US crude for May delivery was down 58 cents at $98.32 a barrel at 0610 GMT in electronic trading on the New York Mercantile Exchange. The contract dropped 27 cents to settle Thursday at $98.90.

Traders have zoomed in on data showing that US crude supplies rose by nearly 6 million barrels in the week ended March 14. Oil production continues to rise, but refineries are converting less of it to gasoline and diesel because they're undergoing seasonal maintenance.

The US dollar has strengthened against the euro and other currencies since the Federal Reserve's new governor Janet Yellen this week suggested interest rate hikes could come relatively quickly after the Fed ends its extraordinary stimulus policy.

A rise in the dollar makes crude more expensive in terms of other currencies.

Brent crude, used to set prices for international varieties of crude, was down 31 cents to $106.14 a barrel.

In other energy futures trading in New York:
- Wholesale gasoline fell 0.7 cent to $2.882 a gallon.
- Heating oil shed 0.7 cent to $2.906 a gallon.
- Natural gas dropped 3.6 cents to $4.333 per 1,000 cubic feet.