The average national price of diesel fuel jumped 7.5 cents to $2.626 a gallon, while gasoline soared 12.2 cents from last week to $2.505, the Department of Energy said Monday.

Just three days after saying it would suspend producing diesel engines for Ford Motor Co., Navistar International Corp. said it would resume production because of a court order from a Michigan judge.

The Ontario Trucking Association said Tuesday that an apparent diesel fuel shortage in the province was causing concern to truckers.

Retail diesel fuel’s national average price rose for a fourth straight week, jumping 6 cents to $2.551 a gallon, the Department of Energy said Monday.

Navistar International Corp. said Monday it is suspending production of a diesel engine it builds for Ford Motor Co. because Ford has stopped honoring contract terms.

The average national retail price of diesel fuel rose 1.5 cents to $2.491 a gallon, the Energy Department reported Tuesday.

Sweden-based truck maker Volvo AB has agreed to buy Japan’s Nissan Diesel Motor Co. for $1.1 billion to add production in Asia, Bloomberg reported Tuesday.

ARLINGTON, Va. — American Trucking Associations said last week it would become more vocal in its support for increased fuel efficiency in heavy trucks and ratified an agreement with the biodiesel industry to promote that fuel at the federal level.

The average national price of retail diesel fuel jumped 4.1 cents to $2.476 a gallon, the Department of Energy said Monday.

SAN ANTONIO — Truck-stop industry officials meeting here said their main focus this year would be preparing for the expected increase in biodiesel use.