FOREIGNERS are scrambling to leave Japan as nuclear fears mount but airline schedules are in chaos after dozens of carriers cancelled and redirected flights away from Tokyo.

International companies have set up evacuation plans in Tokyo and parts of northern Japan and many foreign groups were moving operations to the south and giving staff the opportunity to leave the country.

China has been quick off the mark and has been the first to start a large-scale evacuation of its citizens from affected areas, sending buses to four prefectures: Miyagi, Fukushima, Ibaraki and Iwate to evacuate nationals.

The country was taking people to Toyko's Narita airport or Nigata airport on the northwest coast to board flights to China.

About 33,000 Chinese nationals live in the disaster-hit Japanese prefectures, the China News Service said. China successful lifted 30,000 of its citizens out of Libya when fighting broke out several weeks ago.

The Chinese embassy in Tokyo said it was taking the actions "owing to the seriousness of, and uncertainty surrounding, the accident at the Fukushima nuclear plant at present" and "in accordance with a highly responsible attitude towards the personal safety of Chinese citizens."

"Chinese embassy and consulates in Japan have dispatched several working groups to the disaster-stricken areas to visit the affected Chinese nationals and help with the evacuation," Xinhua news agency reported.

So far, China has not yet received any casualty report of its citizens in Japan.

Airlines are trying rescheduling and flights to Tokyo's Narita and Haneda airports to avoid overnight stays to avoid having staff and planes on the ground to avoid possible radiation as well as aftershocks.

Air China has denied reports it was cancelling blocks of flights but said that "one or two" has been halted. Taiwan's EVA Airways cancelled some flights to Tokyo and Sapporo. Lufthansa has re-directed Tokyo flights to Nagoya and Osaka.

China also sent a 15-member international rescue team to Japan on Sunday, while local governments and China's chapter of the Red Cross have announced separate donations to aid the quake relief actions in Japan.