The Organization of the Petroleum Exporting Countries (OPEC) said it is operating close to full capacity and has little power to lower refined oil product prices -- particularly diesel -- on open world markets.

Saudi Arabia reportedly backs a proposal for an increase in cartel crude supply limits of 500,000 barrels per day, or 2 percent. But Saudi oil minister Ali al-Naimi said his country was already pumping as much as it could sell and blamed refinery bottlenecks for rising costs. "Everybody is concerned about middle distillates," he said, referring to the refined products of diesel, jet fuel and heating oil.
Traders said crude prices are heading back toward their April peak of over $58 after slipping to $46.20 in May, the lowest seasonal period for global demand. The average price for the year so far is nearly $51 a barrel, up from $41.47 on average in 2004 and $30.99 in 2003.
Diesel at the pump hit a U.S. average of $2.27 a gallon on Monday, up 4.2 cents for the week and 56.5 cents per gallon from a year ago.