Blowfish can be lethal if toxins in its organs are released / EPA

Fugu's active ingredient is tetrodotoxin, a poision many times more poisonous than cyanide

It's ugly, expensive and poisonous enough to induce respiratory paralysis and death, but the blowfish has long been one of the more desirable items on Japanese seafood menus.

Good restaurants in central Tokyo charge nearly £100 a pop for a sashimi meal of fugu, the Japanese name for one of nature's most toxic treats.

Japanese fugu chefs are an exclusive guild, licensed to carefully gut the fish of the liver, ovaries and other parts where the poison lurks.

Now in a move that has sent some blowfish restaurants into toxic shock, Tokyo's government says it is deregulating the trade, allowing the fish to be sold in premises without a licensed chef. "Regulations no longer meet the needs of contemporary fugu distribution," sniffed an official with the government's public health bureau.

Fugu lovers have for years been bypassing the capital's licensed – and expensive – eateries by ordering from other parts of the country where the fish is freely available. The licensing system, which forces chefs to train for at least two years, is outdated and costly, say opponents.

"The strict regulations have protected Tokyo's fugu industry, and this has kept the fish's prices high," restaurant-chain owner Daichi Sakamoto told the Yomiuri newspaper.

Some Tokyo proprietors warn, however, that deregulation could backfire. "I think the government needs to be aware that people still die from eating this fish," said the proprietor of the Genpin Fugu restaurant in Tokyo's Shinjuku district. "It's very odd to take chances with lives just to save a bit of money."

Fugu's active ingredient is tetrodotoxin, a poison many times more toxic than cyanide – it reportedly induces paralysis while the victim stays wide-eyed and conscious.

Over the years, hundreds of people have died after dining on the chewy white meat. Fatalities peaked after the Second World War when starving Japanese riffled restaurant rubbish bins for food. Fugu restaurants pushed for the government licensing system, which was introduced in 1949. Since then, poisonings have fallen to the current 20 or so a year, mainly by people gutting and cooking the fish at home.

"I'll rather pay a bit extra to be safe," says Masaru Kondo, a fugu veteran.