Environmental campaigners have called for a worldwide ban on the sale of endangered tuna until stocks recover.
Last week nearly 100 Greenpeace activists stormed the European Seafood Exposition in Brussels - the largest trade show of its kind in the world - to demand that fish such as bluefin be withdrawn from sale until stocks are replenished.
The demonstrators used fishing nets and chains to disrupt public access to the stands of the Mitsubishi Corporation, bluefin specialist Ricardo Fuentes, Dongwon Fisheries, Maltese company Azzopardi Fisheries and Moon Marine from Taiwan.
"These companies are responsible for pushing tuna towards commercial extinction," said Willie Mackenzie of Greenpeace.
"Unless urgent action is taken, overfishing and the destructive and short-sighted methods of these companies could see the end of the tuna trade, because there won't be enough left. Put simply, there are too many ships chasing too few fish."
Greenpeace has backed the creation of dedicated marine reserves to allow fish stocks to recover.
The organisation also claimed that globally up to 90% of stocks of large predatory fish - including tuna, swordfish, cod and halibut - have already been wiped out.
A spokeswoman for WWF said the organisation had also been lobbying vociferously for bluefin tuna to be protected. "There is a massive problem with illegal, unregulated tuna fishing, and the amount of overfishing is greatly underestimated," she said.
The UK's largest supermarkets had already been persuaded not to sell bluefin tuna, but it was still on sale in some specialist and independent retailers, she added, urging all shops to stop stocking the products.
Last September the Marine Stewardship Council gave approval to its first MSC-certified tuna farm, Albacore in the United States.
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