Customers of Ikesu Onsen, a traditional Japanese bathhouse in Tsushima in Aichi prefecture, have had to delay their daily dips due to the Iran war.

The sento, or public bathhouse, has been forced to push back its opening time by an hour since late March because of an unstable supply of fuel oil, according to Kyodo.

Monthly delivery has been halved from about a tonne, leading the number of customers of the family-run 97-year-old sento to fall to around 10 per day.

“It’s a major blow,” its 57-year-old operator, Atsuko Matsui, told the news agency. “If we are told [by the supplier] ‘this amount at this price,’ we have no choice but to accept it.”

Like Iketsu, sentos across Japan have had to shorten opening hours or close temporarily as the global energy crisis bites.

Japan, which imports over 90 per cent of its crude oil from the Middle East, is facing shortages since Iran effectively closed the Strait of Hormuz in retaliation for US-Israeli air strikes in March.