The average price of diesel increased 1.1 cents per gallon nationwide, according to figures released by the Energy Information Administration.
The average price of $1.595 was the highest since March 31, 2003, when it was $1.602.
The price increased in every region of the country except for the West Coast, where it fell 0.1 cents to $1.788. The Lower Atlantic states saw the biggest increase at 1.8 cents.
The Gulf Coast states have the chepest diesel at $1.536.