Retailers' standards with regards to safety, quality and traceability in fish supply are placing increasingly bewildering burdens on developing countries, the UN has heard.

The 10th meeting of the FAO Sub-Committee on Fish Trade was told that responsibly managing the global fish trade was becoming ever harder.

Developing countries in particular noted that complying with such standards involves significant financial and technical burdens, that vary greatly from market to market.

"We heard from all the delegations that ensuring consumer safety and bringing products to market that come from sustainable fisheries is of course extremely important," said chairman Jorge Zuzunaga. "It's just that, as one delegate put it, a 'bewildering array' of different standards are being applied to fish imports, which can create problems - especially for countries where production comes from small-scale fishers."

The problem is compounded by the fact that most of the fish that is consumed worldwide is consumed by developing nations. The value of the international fish trade increased from $15.5bn in 1980 to $71bn in 2004, according to the UNFAO.

Developing countries have particularly benefited, with net earnings increasing from $3.4bn to $20bn over the same period. This income exceeds the net foreign exchange revenue they earn from any other food commodity.

The UN wants import standards to be fair and based on good science, and developing countries to get the resources and know-how to meet them from developed countries.

Meanwhile, UNFAO data show that out of the 600 major commercial species, 25% are either overexploited, depleted or recovering from depletion. About 200 million people worldwide earn a living from fishing.