National diesel prices jumped 2.4 cents this week after last week’s much-needed 1.1-cent decline, according the Department of Energy.

The steepest increase was reported in the Rocky Mountains, with a 3.4 cent increase to $1.67 per gallon. California saw a 2-cent decrease, however, to $1.85 a gallon.

Diesel prices are up 7.3 cents since OPEC’s February announcement that it will cut oil production by April 1 to keep prices high. It remains uncertain whether or not OPEC will implement this quota as gas and diesel prices approach pre-Iraq war highs.