Toyota Motor Co is set to lose its crown as the world's largest automaker after Japan's earthquake and nuclear disaster slashed local output by almost two-thirds in March.   

Japan's auto sector has been hit hard by the disaster due to a shortage mostly of electronic and resin-based parts in the wake of the magnitude-9.0 earthquake and resulting tsunami, as well as damage to a major nuclear plant which disrupted power supplies.

Toyota said last week it could take until the end of the year before production fully recovered.

The world's largest automaker said domestic production fell 62.7 percent to 129,491 units in March, while Japan's No.2 Nissan Motor Co said its corresponding figure fell 52.4 percent to 47,590 units.

Honda Motor Co said domestic production shrank 62.9 percent to 34,754 vehicles. 

Toyota is now almost certain to lose the top producer ranking it has held since 2008 to General Motors this year. Toyota sold 8.42 million vehicles last year, topping GM's 8.39 million.

Koji Endo, managing director of Advanced Research Japan in Tokyo, said Toyota was now on track to post sales of around 6.5 million units this year.

"Most likely GM will produce 8 million-plus and Volkswagon will produce around 7 million, so most likely Toyota will be third, GM will be first," Endo said.

Toyota, criticised by some analysts and investors for its aggressive expansion in the early 2000s, played down the prospect of losing its top ranking.

"When Toyota became No. 1 there were no champagne corks going off here," said Toyota spokesman Paul Nolasco. The March sales were the worst since records began in 1988, he added.

Japanese automakers have not forecast what impact the production cuts will have on earnings, but analysts have been slashing their forecasts since the disaster.

"In overseas markets consumers have choices and (non-Japanese makers) probably will take some share, but I think it is an open question if those will be sustainable or temporary share changes -- my guess is that they will tend to be temporary," said Christopher Richter, an auto analyst at CLSA Asia-Pacific Markets in Tokyo. - Reuters