State officials in Minnesota have granted a three-week reprieve from a mandate that all diesel fuel sold in the state contain at least 2 percent biodiesel. The requirement was suspended Dec. 23 after truck drivers complained of fuel filter problems in cold temperatures. The mandate, which went into effect Sept. 29, was hailed by state officials as a step toward breaking the nation’s dependence on foreign oil. Minnesota was the first state to adopt a biodiesel requirement. State officials are investigating the problems reported by the truckers. It's uncertain whether the fuel filter plugging is due to the addition of biodiesel.