Europe's eel populations face being wiped out because France has refused to accept a continent-wide complete ban on the export of glass eels.

European countries are trying to hammer out a deal to allow eel populations to recover – eel numbers have declined by more than 90 per cent in the past 20 years.

Britain has imposed its own temporary ban on fishing for mature eels, and places quotas on the capture of glass eels, the tiny translucent juvenile fish that are born in their millions in the Sargasso Sea and travel to European estuaries to mature into adults.

But demand from China for glass eels has pushed up prices to more than €1,000 (£850) a kilo – similar to cheap caviar – providing fisheries with a major incentive to continue trawling.

Last year, the Convention on International Trade in Endangered Species called on trade in European eels to be controlled. The EU's Scientific Review Group has recommended a complete ban on exports this winter. But at a meeting in Brussels, France – Europe's largest eel exporter – refused to sign up to a ban. The result is that no quota has been set just as the eel season kicks off.

Campaigners are concerned that France will continue to fish eels in unsustainable numbers this winter. French fishermen have threatened to go on strike if a ban is brought in.

Compared to Britain, which accounts for only 2 per cent of Europe's annual eel catch, France is a major exporter of glass eels to Asia and uses mechanised trawlers in the Bay of Biscay to fish for them.

Last year the total Cites-recommended French export quota was 14 tonnes, but campaigning groups that track fishing exports accuse France of shipping more than this to China alone.

"Exploitation of eels by any one member state impacts the region's entire eel population and therefore management purely at the national level makes no sense," said Stephanie von Meibom, the European programme co-ordinator of the conservation group Traffic. "It is inconsistent with EU policy which emphasises harmony, consistency and coherence between member states."

Pollution, climate change and unsustainable fishing practices have led to a 90 per cent drop-off in worldwide eel populations, scientists say.

Although the Japanese usually insist on eating their indigenous eels, the Chinese and Koreans are less fussy and import millions of European glass eels, which are then grown to maturity before being eaten.

Iceland, Norway, Ireland, Holland, Britain and parts of Spain have brought in their own quotas or bans. But the comparatively lax approach by the French authorities has placed pressure on other European fishermen to flout those bans.

Peter Wood, managing director of UK Glass Eels, accused the French of behaving selfishly and of feeding off the sacrifices of other nations. "They do seem very keen in France to continue to export everything to Asia, and that seems to me a huge loss of a valuable resource," he said.

"They've got this idea that they have this resource of glass eels and it is theirs to do with as they see fit. But it's a collective resource. Most of the glass eels came from breeding stock from other European nations. Some have come from comprehensive restocking programmes in the past, like in Northern Ireland and Sweden. Stock from these countries has gone back to the Sargasso Sea to breed."