The UN body overseeing commerce in endangered wildlife today rejected a proposal to outlaw international trade in eastern Atlantic and Mediterranean bluefin tuna, a sushi mainstay in Japan.

The controversial proposal for so-called Appendix I status was quashed with 68 votes against, 20 in favour and 30 abstentions at a meeting in Doha of the Convention on International Trade in Endangered Species (CITES).

The measure would have needed the support of two-thirds of the nations present to pass.

The EU had been backing the proposed ban, having over-ruled opposition from Malta, the biggest exporter of tuna in Europe.

Bluefin tuna stocks in the Atlantic and Mediterranean have crashed, with populations declining by up to 80 percent from only three or four decades ago.

Japan, which buys three-quarters of the global catch of bluefin tuna, lobbied successfully in Doha and elsewhere to block the proposal, put forward by Monaco and backed by the United States and the European Union.

An EU proposal that would have delayed the Appendix I listing by 18 months was likewise rejected by an even wider margin: 72 "no" votes, 43 "yes" and 24 abstentions.

Anticipating a possible defeat, Monaco was set to table amendments to its proposal, while Europe -- backed by Norway -- was poised to call for the formation of a working group to hammer out a compromise.

But in a procedural move, Libya short-circuited the debate and called for an up-or-down vote on the original proposition.

"This is very disappointing and very irresponsible," said Sue Lieberman, policy director for the Pew Environment Group in Washington.

"The fate of tuna is now, once again, in the hands of ICCAT," she said, referring to International Commission for the Conservation of Atlantic Tunas.

ICCAT has "demonstrated over a period of decades" its inability to enforce its own quotas for tuna catches, she added.