Toyota has suffered its first quarterly sales decline since the months after the September 2001 terrorist attacks, underscoring that even Japan's biggest carmaker will not escape the worldwide motor industry slump.

The rare reversal - it was only the second quarterly fall since it began tallying comparable figures in 1999 - came as demand for cars and trucks in the US, its biggest market, tumbled towards two-decade lows. European and Japanese sales have also shrunk.