Japanese automakers are planning to idle U.S. plants and are considering shipping more parts from the U.S. to Japan after the March 11 earthquake, tsunami and subsequent crisis at the Fukushima Dai-ichi nuclear plant have disrupted parts deliveries.

Toyota told U.S. workers on Wedneday that some of their plants will be idled soon because of the disruptions.

"We don't have specifics on when, which plants, how many days," said Toyota spokeswoman Carri Chandler. "We have eliminated overtime and Saturday production as a precautionary step to conserve parts from Japan."

This is more evidence that the earthquake's economic aftershocks are becoming significant in the U.S.

American consumers are paying at least $2,000 more for a Toyota Prius than they would have paid before the crisis began and forced the automaker to halve production at all its assembly plants in Japan, said Jesse Toprak, who tracks the prices consumers pay for cars at TrueCar.com.

"Prius went from selling about $300 under invoice three weeks ago to selling right at the MSRP since the earthquake," Toprak said.

The manufacturer's suggested retail price is $24,050.

While dealers say they still have ample supplies of the popular hybrid, the higher sales prices reflect concerns that the car will soon be in short supply.

Toyota, Honda, Nissan and Subaru are struggling to get their plants and suppliers up and running in the wake of the 9.0-magnitude earthquake that killed more than 9,400 people. Toyota plans to keep all its assembly plants idle through this week. Two Honda assembly plants and a motorcycle plant have halted production at least through this weekend.

Nissan CEO Carlos Ghosn said Wednesday that about 40 of its parts suppliers are not operational, and Nissan might not be able to resume production at its engine factory in Iwaki, Fukushima. Nissan is considering shipping more engines from Decherd, Tenn., to Japan.

Toyota said Wednesday the April sales launch in Japan of the all-new Prius V minivan has been postponed. The Prius V is scheduled to go on sale late this summer in the U.S. Toyota said no decision has been made on changing that schedule.

Tammy Darvish, who owns four Toyota dealerships in the Washington, D.C., area, said Toyota has asked that dealers not change option and accessory orders for any vehicles made for the next twomonths.

Other models assembled in Japan for which inventories are running low include the Nissan Rogue, Murano, Juke and Cube; Acura TSX; Subaru Impreza and Mazda5.

So far, General Motors is the only domestic automaker that has been affected in the U.S. Production has stopped at its Shreveport, La., assembly plant, and production of one engine has been reduced at its Tonawanda, N.Y., factory.

But Ford and Chrysler could face adjustments soon.

Craig Fitzgerald, automotive supplier analyst with Plante & Moran, predicted there would be U.S. production stoppages over the next eight weeks.