Shipping along the Yangtze River, one of China's most vital waterways, has been closed at some points to prevent ships being grounded due to low water levels.
Officials of the Yangtze River Waterway Bureau said they closed the section from the major inland port city of Wuhan to Yueyang, about 115 miles upriver.
It is unclear how many ships will be affected by the delays or how long they might last. Photographs in recent days have shown lines of barges and ships lined up along the river, waiting to move up or downstream.
Much of central, northern and south-western China has been parched by drought, ruining crops and causing severe water shortages for millions living in the region.