Tokyo, Jul 24 (IANS): Japan's weather agency has declared the heatwave sweeping the country a natural disaster, with at least 65 deaths recorded in the past week.

According to official figures released on Tuesday, more than 22,000 people were hospitalized, with temperatures soaring to historic levels, the BBC reported.

This is the highest number of people to have been given hospital care for a heat wave in 10 years when official records first started being kept.

High temperatures were recorded across the country since mid-July and Monday reached a historic maximum of 41.1ºCelsius in the city of Kumagaya in Saitama Prefecture.

Figures provided by the Fire and Disaster Management Agency (FDMA) said that of the 65 deaths, six were in Saitama.

The Japan Meteorological Agency warned that temperatures of 35ºCelsius or higher would continue until early August. "We are observing unprecedented levels of heat in some areas," agency spokesman Motoaki Takekawa said, adding that the heatwave was "a threat to life and we recognise it as a natural disaster".

In Japan's most populated prefecture of Tokyo alone, 1,979 people had been hospitalized because of the heat wave.

With less than half of Japan's public schools equipped with air conditioning, government spokesman Yoshihide Suga said the summer holidays could be extended to protect pupils.

The Japanese people have been advised to drink plenty of water, use air conditioning and rest often.