The 269-kg fish, bought by restaurant owner Kiyoshi Kimura, carries enough flesh for an estimated 10,000 pieces of sushi

This article is more than 8 years old

This article is more than 8 years old

A Japanese restaurateur has parted with almost half a million pounds for a single bluefin tuna at the first auction of the year at Tokyo's Tsukiji market.

Kiyoshi Kimura, who runs a chain of sushi restaurants, paid 56.5m yen (£473,000) for the 269-kg fish, which carries enough flesh for an estimated 10,000 pieces of sushi.

The sum is almost twice the 32.49m yen paid at last year's opening auction, a largely symbolic affair and not – diners will be relieved to hear – an accurate reflection of wholesale fish prices.

Japan has come under pressure to decrease its catch of Pacific and Atlantic bluefin, whose stocks have reached dangerously low levels, according to campaigners.

Kimura, however, said he has made his record-breaking bid in an attempt to "liven up Japan" as it attempts to recover from last year's tsunami.

"Japan has been through a lot the last year due to the disaster," he said. "It needs to stay strong. That's what I tried to do and I ended up buying the most expensive one."

The businessman, who runs the Sushi-Zanmai chain of 46 restaurants, also claimed he was acting on behalf of homegrown sushi lovers, who for the past three years have seen the first big fish of the season snapped up by overseas bidders.

Last year, the Hong Kong restaurateur Ricky Cheng joined forces with an upmarket sushi restaurant in Tokyo to produce the winning bid.

But this year Kimura said his restaurants would slice up and serve the entire fish – caught in Oma off the northernmost tip of the main island of Honshu – in Japan, rather than let it go overseas.

Although the restaurant needs to sell each piece of sushi for more than 6,000 yen to break even, Kimura is already selling prized slices of fatty otoro for a far more affordable 418 yen each, with the cheaper akami cuts going for about 130 yen apiece.

"It's unbelievable, Kosuke Shimogawara, a diner, told Associated Press. "President Kimura is so generous. All I can say is thank you."

Japan consumes about 80% of Pacific and Atlantic bluefin tuna, and has been accused of stifling international attempts to dramatically reduce fishing quotas or ban the trade altogether.