A U.N. panel said Monday it has lifted an export ban on three types of caviar, including the highly prized beluga variety.

Willem Wijnstekers, the head of the U.N.-sponsored conservation body CITES, said countries bordering the Caspian Sea had improved their monitoring of caviar trading and would release millions of young fish into the body of water, allowing limited trading to resume.

Nevertheless, he said the decision to grant Azerbaijan, Kazakhstan, Iran, and Russia permission to export 4.15 tons of beluga must be accompanied by further moves to combat declining sturgeon stocks.

CITES "will be using all the tools at its disposal to bring this trade onto a more sustainable footing," Wijnstekers said.

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But the move was condemned by environmentalists as "irresponsible."

"We're extremely disappointed in this decision by CITES," Julia Roberson of the conservation group Caviar Emptor told The Associated Press. "We view this as another nail in the coffin for this species."

"The most recent information that we had was that the populations of beluga sturgeon from 2004 to 2005 had declined by 45 percent, so it's very irresponsible of CITES to be reopening trade," she said.

Last year the body — U.N.'s Convention on International Trade in Endangered Species of Wild Fauna and Flora — refused to provide export quotas for caviar from the Caspian Sea in order to help protect the endangered fish from which the eggs are taken.

In January, CITES loosened restrictions on three other types of caviar than beluga, which can cost upward of $5,000 a pound, depending on taste and quality.

At the time the U.N. panel said the income earned from the sale of sturgeon products throughout 2007 "should provide both an incentive and the means to pursue the long-term recovery of this commercially and ecologically valuable natural resource."

Monday's announcement will also permit China and Russia to export about 3.5 tons of Amur sturgeon roe and 4.6 tons of Kaluga sturgeon roe caught in the Heilongjiang-Amur river basin shared by both countries.

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