More than 130 dead amid flooding and mudslides in Japan
Prime Minister Shinzo Abe has cancelled a foreign trip to oversee the emergency response.
More than 130 people have died after heavy rainfall caused flooding and mudslides in south-western Japan.
Rescuers are searching for more than 50 unaccounted for people in and around the hardest hit Hiroshima area.
Work under the scorching sun was hampered by mud and heat, and shipments of relief goods were delayed by damaged roads and transportation systems, especially in areas isolated by the disaster.
"No water, food, nothing gets here," Ichiro Tanabe, a 73-year-old Kure resident, told the Mainichi newspaper. "We are going to be all dried up if we continue to be isolated."
Some of the thousands of residents who had been evacuated, including some rescued from their rooftops, began cleaning up after the rain stopped Monday.
Japan's chief cabinet secretary Yoshihide Suga said the government set up a taskforce and was spending 2 billion yen (£13.6 million) to hasten deliveries of supplies and other support for evacuation centres and residents in the region.
Earlier on Tuesday, the Self-Defence Force ferried seven oil trucks from Hiroshima to Kure, a major industrial city whose 226,000 residents were cut off from the rest of the prefecture due to the disaster.
Thousands of homes were still without clean water and electricity in Hiroshima and other hard-hit areas. Residents lined up for water under the scorching sun as temperatures rose to 35C (95F), raising risks of heat stroke.
Residents sheltering at a local school in Hiroshima's Yano district were provided with water, blankets and phone chargers.
Prime Minister Shinzo Abe cancelled a planned trip to Europe and the Middle East to oversee the emergency response. The government mobilised 75,000 troops and emergency workers and nearly 80 helicopters for the search and rescue effort, Mr Suga said.
Assessment of the casualties was slowed down by the scale of the area affected. Officials in Ehime prefecture asked the government to review its weather warning system, noting that rain warnings were issued after damage and casualties had already occurred. The Japan Meteorological Agency said as much as 10cm of rain per hour fell on large parts of south-western Japan.