The surge in the wholesale price of tuna has started to slow, apparently because of slumping consumption amid the deepening recession, industry sources said.

At Tokyo's Tsukiji fish market, the rise in the price of frozen tuna in October slowed to 8.9 percent compared with the same month last year, after sales decreased 19.2 percent to 3,000 tons.

In August and September, prices were up more than 20 percent compared with last year, because of sharp rises in crude oil prices and lower quota caps on catches.

"The price hikes have drastically slowed down," said a Tsukiji market source.

The price of frozen bigeye tuna has fallen below the level of ¥1,000 per kg, down nearly ¥100 from its peak in August.

"The prices of tuna were already high. (Market buyers) are very worried that consumers may stop buying if the prices go up further," said another market source.

One wholesaler specializing in high quality tuna said his firm can now sell only half the amount compared with last year to high-end sushi bars in Tokyo's Ginza district because of fewer customers, including from foreign firms.

"We can't get by because we are hit both by the reduced catches and price slowdown at the same time," said a spokesman of the Japan Tuna Fishers Cooperative Association.