Tokyo, Sep 22 (IANS): A powerful tropical storm was on Sunday moving towards the coasts of Japan and South Korea, bringing with it heavy rains and strong winds, and forcing the cancellation of nearly 1,000 flights in the two countries.

The Japan Meteorological Agency has not classified the storm as a typhoon so far, terming it a tropical storm which formed in the South China Sea and is moving in a north-northeasterly direction, between the coasts of Japan and South Korea, reports Efe news.

The storm, Tapah, is moving at a speed of 30 kph and generating winds of up to 108 kph and gusts of 162 kph.

It caused heavy rains - more than 400 mm - since Saturday on the Japanese island of Kyushu.

This is the 17th tropical storm in the region this season.

According to Japanese state broadcaster NHK, around 400 domestic flights were cancelled on Sunday.

South Korean authorities are also in a state of alert, with heavy rains of up to 476 mm lashing the worst-hit regions of the country.

Around 500 flights were expected to be cancelled in South Korea on Sunday due to Tapah.