The nation's moving companies are warning Americans they may find it tough to move this summer because "critical" shortages of diesel fuel are throwing pickup and delivery schedules into chaos.

The companies have asked the government to go easy on movers who can't pick up or deliver on time because of shortages.

The American Movers Conference, in letters to the Interstate Commerce Commission and the Department of Energy, said that "in many parts of the country drivers are required to allocate as much as 30 percent of their time looking for fuel or sitting in lines waiting for fuel."

"The result is near chaos for a carrier in planning when a vehicle will arrive at a destination and be ready to pick up another shipment," the group said.

It warned that if Energy Department projections of low diesel supplies for the next six months come true the industry will be in "disarray" and "consumers will be terribly alarmed."

The trade association asked the department to grant movers a special exemption permitting them to buy the same amount to diesel fuel they have in the past.

The large coast-to-coast shippers have their own fuel supplies, garages and filling stations, but they have been cut back in the amount of diesel fuel they can buy. Smaller operators have to vie for fuel with other truckers at any station selling it.

In addition, the group asked the ICC to use discretion in enforcing its rules calling for shipments to be picked up and delivered on time. In cases where fuel is in short supply, it said, the ICC should not enforce the rules and slap the movers with fines which violations otherwise would bring.

The group said "critical shortages" of diesel fuel are showing up across the country.

"Carriers don't know when or how long it will take drivers to get to a destination and are unable to tell consumers when trucks will be available to pick up new shipments," it warned. "Consumers are going to be frustrated because deadlines are not going to be met."