Honda Motor Co <7267.T> and Mazda Motor Corp <7261.T> on Thursday became the latest major automakers to say they would resume some production in Japan after halting plant operations following the earthquake and tsunami of March 11.

Honda said it would resume production of parts for overseas use on April 4, and production at all its car factories on April 11. Operations are scheduled to resume at about 50 percent of its original plan.

Honda also said production cuts at its plants in the United States and Canada would last through April 15. The company warned that output could still be disrupted after that date because of the uncertainty around the supply of parts from Japan.

Honda has not decided when it will resume full-scale operations, a company spokeswoman said. She also declined to specify which models the company will produce.

Mazda Motor Corp said it plans to restart limited production of vehicles from April 4 at its Hiroshima and Hofu plants. A decision on the resumption of full-scale production of both parts and vehicles has not been made.

A Mazda spokesman declined to say if the parts it is using are being produced by its suppliers or if they are coming out of suppliers' inventory. Mazda also declined to comment on which models it would begin producing, or how many.

In resuming operations, Honda and Mazda follow rival automakers Suzuki Motor Corp <7269.T> and Fuji Heavy Industries Co <7270.T>, manufacturer of Subaru cars, which both restarted partial production earlier on Thursday.

Japanese automakers including Toyota Motor Corp <7203.T> and Nissan Motor Co <7201.T> said earlier this week it would be some time before they could return to full production.

USED CAR PRICES SHOOT UP

The earthquake, ensuing tsunami and nuclear crisis have revealed flaws in just-in-time production, which involves keeping low quantities of parts and supplies on hand to avoid high costs.

This week, Toyota told its North American dealers it would control the allocation of certain parts, including steering wheel covers and shock absorber.

We are getting our plants back online and our parts production back online, but at this point, we're still trying to gather information on the situation of our suppliers and their suppliers, said Bill Kwong, a Toyota spokesman in California.

Toyota also said on Thursday it would raise retail prices for Toyota, Lexus and Scion brand models sold in the United States, but not because of the earthquake and its aftermath. Rather, Toyota said, the price rise was due to the strong yen relative to the U.S. dollar.

Kwong said it was too early to say for sure if Toyota will raise new vehicle prices for the U.S. market.

We're still determining the details of how production will be affected in Japan, said Kwong.

U.S. car shoppers are expecting the parts shortages will lead to a dwindling supply of small, fuel-efficient cars at a time when gas prices are rising, an automotive analyst for the National Automobile Dealers Association said on Thursday.

This has helped push up the prices of used cars, NADA Used Car Guide analyst Jonathan Banks said. From March 11-28, auction prices on compact cars, such as the Honda Civic and Ford Motor Co's Focus, rose 11 percent.

The price of used vehicles sold at auction increased 5 percent during that time, higher than the expected 3 percent, Banks said.

(Reporting by Chang-Ran Kim; additional reporting by Deepa Seetharaman and Bernie Woodall in Detroit; Writing by James Topham; Editing by Joseph Radford, Maureen Bavdek, Gary Hill)