The Japan Meteorological Agency said temperatures would rise this weekend to well above freezing in affected areas, some of which had nearly four metres (13 feet) of snow piled up.

"We are worried that rains, coupled with water from melting snow, could trigger landslides," said an agency official.

About 80 percent of those who have died in the largely rural areas were over the age of 60, the Fire and Disaster Management Agency said. Many have fallen to their deaths while clearing snow from roofs creaking under its weight.

In Niigata prefecture northwest of Tokyo on Saturday, a 72-year-old man died when his two-storey house collapsed under the weight of snow, a police spokesman said.

And a 64-year-old man died in Nagano prefecture, also northwest of Tokyo, when he fell off the roof of his storehouse.

One woman died after being caught up in a snowblower in the northern prefecture of Akita, media said.

Both the public broadcaster NHK and Kyodo news agency put the death toll in recent weeks from snow-related accidents at 90, the highest in more than 20 years.

Several avalanches were reported in northwestern Japan on Saturday, including one at a ski resort in Shimane prefecture, but there were no reports of casualties, police said.

Shortly after returning from a trip to Turkey on Friday, Prime Minister Junichiro Koizumi instructed his government to work out measures to deal with snow damage.

The government says it is sending 11.3 billion yen ($99 million) to local authorities to help them clear snow from roads.

Government officials fear that prices of products such as kerosene and vegetables could shoot up due to the bitter cold.

A farm ministry survey carried out between Jan. 4 and Jan. 6 showed cabbage was 50 percent more expensive than usual and leek prices were up 40 percent.