The national average U.S. retail price of diesel fuel rose to $1.763 from the previous average of $1.745, the Department of Energy reported May 17.

Once again, the highest prices in the nation were in California, where the average cost is $2.340. About 100 drivers in Concord, CA, gathered during the weekend to protest the high prices, among other issues.

Meanwhile, it appears protests at rail yards, interstates and port facilities in California, Virginia and Texas have stalled for the time being. However, drivers in those areas vow to continue protests if their demands are not met and if prices continue to rise.

Other prices included New England, at $1.804; $1.951 in the Rocky Mountain region; the Central Atlantic region, at $1.791; and on the West Coast, where the average price is $2.250.

Comparatively lower but steadily rising prices were found in the Lower Atlantic region, where the average price is $1.652; the Midwest, at $1.688; the Gulf Coast, at $1.664; and the East Coast, at $1.700

A repeat of times past?

Meanwhile, OPEC is concerned that soaring oil prices could slow global growth, but believes current 13-year highs are largely out of its control, the group's president, Purnomo Yusgiantoro, said May 16, as reported by Reuters.

"OPEC is very concerned with the current high oil prices, and we'll try to avoid the same global recession as what happened in 1973," Purnomo, who is also Indonesia's oil minister, told a news conference.

In the fallout of the 1973 Yom Kippur War, in which Arab forces were defeated by Israel, OPEC raised oil prices tremendously, triggering massive economic problems for oil-importing nations.

OPEC members will meet informally in Amsterdam next week to discuss a proposal from Saudi Arabia, the world's largest oil producer, to hike output by 1.5 million barrels per day from the current ceiling of 23.5 million.

Although Kuwait has agreed to the plan, most OPEC members have not yet decided whether to back the measure, Purnomo said.

Still, OPEC's ability to bring down global oil prices, which are currently trading above record $40 per barrel levels, is limited, Purnomo said.

OPEC pumps a third of the world's oil. The group's officials argue that there is little they can do, citing geopolitics and a tightness in U.S. gasoline stocks as the forces driving high prices.