The average price of a gallon of diesel fuel rose 4.4 cents last week to $2.616, according to weekly figures released by the U.S. Energy Information Administration.
It's the seventh weekly increase in a row and the highest diesel prices have been since Nov. 24, when the agency's reported average was $2.664. The price of diesel has risen 43.1 cents during that seven-week period.
Meanwhile gasoline prices have risen more than 65 cents per gallon over the last 11 weeks.
Oil prices, on the other hand, fell Monday to close at $66.93 a barrel on the New York Mercantile Exchange. Analysts say oil prices are being driven not just by supply and demand, but are affected by perceptions of the global economy and the strength of the dollar.
The World Bank Monday cut its forecast for developing nations' economies, estimating growth at only 1.2 percent this year, marking a steep drops from the previous two years.