Toyota said Tuesday its April-September net profit dived 25 percent, hit by a sharp rally in the yen and as North American vehicle sales fell again, but it upgraded its full-year outlook.

The world's biggest vehicle maker reported a net profit of 946.1 billion yen ($9.1 billion) in the first half of its fiscal year, down from 1.25 trillion yen in the same period last year, while revenue slipped 7.2 percent to 13.07 trillion yen.

However, the Japanese company boosted its full-year to March net profit forecast to 1.55 trillion yen from an earlier 1.45 trillion yen estimate.