Japan's southwestern regions of Okinawa and Amami are bracing for strong gusts and high waves as a large, very strong typhoon approaches.

The Meteorological Agency says that as of 6 a.m. on Tuesday, Typhoon Khanun was 200 kilometers southwest of Minami-Daitojima Island and moving northwest at a speed of 20 kilometers per hour.

The storm had a central atmospheric pressure of 935 hectopascals, and was packing winds of up to 162 kilometers per hour near its center, and peak gusts of 234 kilometers per hour.

Weather officials say the typhoon will gradually change its course westward, and come closest to the Okinawa and Amami regions through Wednesday.

The maximum wind velocity on Tuesday is expected to be 144 kilometers per hour in Okinawa and 90 kilometers per hour in Amami. Peak gusts could reach 216 kilometers per hour.

The officials say that on Wednesday, peak gusts could increase to as much as 234 kilometers per hour in the two regions.

The officials are warning that winds across the regions could be powerful enough to make some houses collapse.

The typhoon is also expected to lash both regions with torrential rain, dumping up to 150 millimeters in Okinawa and 120 millimeters in Amami in the 24-hour period through Wednesday morning, and more rainfall is likely through Thursday.

The officials are warning of violent winds, rough seas and storm surges.

They also warn that the downpour could trigger landslides, flooding in low-lying areas and swollen rivers.

They are urging people to check their local hazard maps and take shelter in sturdy buildings before the wind and rain grow stronger.