Temperatures rose across Japan on Tuesday, climbing to near record highs around 40 C in a number of areas, with the weather agency warning of heat-related illnesses.

With temperatures expected to remain high on Wednesday, the government has issued an alert covering wide areas from eastern to western Japan, requesting people to drink water and avoid going outdoors to prevent heat exhaustion.

The country's record high of 41.1 C was registered in Kumagaya, Saitama Prefecture, in 2018 and was equaled in Hamamatsu, Shizuoka Prefecture, in 2020.

Children play in the water at a park in Tokyo on Aug. 2, 2022. (Kyodo)

On Tuesday, temperatures rose to 39.5 C in Koshigaya, north of Tokyo, and Kofu in central Japan, with central Tokyo seeing a high of 35.9 C, according to the weather agency.

Among the 914 observation points nationwide, temperatures had risen to 30 C or above in 658 locations as of 4 p.m., with the mercury hitting 35 C or above in 224.

Countries across the globe have been battling extreme temperatures in recent weeks. Britain recorded over 40 C in July for the first time, while heat warnings have been issued in dozens of locations in the United States.

Portugal has reported more than 1,000 deaths due to heat-related illnesses.

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